# usefulweb.site

> A network of 111 focused, deterministic tools. Every tool has a human page, a JSON API, an OpenAPI description and an MCP tool that all return the same result (inputs, result, units, assumptions, sources, timestamps).

## Machine interfaces
- Tool catalog (JSON): https://usefulweb.site/api/v1/tools
- OpenAPI (all tools): https://usefulweb.site/openapi.json
- MCP server (all tools + workflows): https://usefulweb.site/mcp
- Pick a tool for a natural-language request: POST https://usefulweb.site/api/v1/tools/prompt-to-tool-router/calculate {"request": "..."}

## Tools
- [HeaderLens](https://headerlens.usefulweb.site/): Is a website down? Multi-region status, redirects, TLS and security headers. API: POST https://usefulweb.site/api/v1/tools/headerlens/calculate
- [Cancellation Navigator](https://cancellationnavigator.usefulweb.site/): Verified steps to cancel Netflix, Spotify, Prime & more, plus a cancellation letter. API: POST https://usefulweb.site/api/v1/tools/cancellation-navigator/calculate
- [Deadline Decoder](https://deadlinedecoder.usefulweb.site/): Find every deadline, required action and consequence in a letter or notice. API: POST https://usefulweb.site/api/v1/tools/deadline-decoder/calculate
- [Decision Simulator](https://decisionsimulator.usefulweb.site/): Compare 2–6 choices by expected value, worst case, best case and minimax regret. API: POST https://usefulweb.site/api/v1/tools/decision-simulator/calculate
- [Form Translator](https://formtranslator.usefulweb.site/): Plain-language help for confusing forms: field-by-field hints and jargon explained. API: POST https://usefulweb.site/api/v1/tools/form-translator/calculate
- [How Long Will It Last?](https://howlongwillitlast.usefulweb.site/): Estimate remaining life of appliances and home components and plan the replacement. API: POST https://usefulweb.site/api/v1/tools/how-long-will-it-last/calculate
- [Is It Worth It?](https://isitworthit.usefulweb.site/): Buy, rent, repair or subscribe? Compare total cost and NPV over the years you need it. API: POST https://usefulweb.site/api/v1/tools/is-it-worth-it/calculate
- [Life Admin Generator](https://lifeadmingenerator.usefulweb.site/): A dated to-do list for moving, marriage, a baby, a new job and other life events. API: POST https://usefulweb.site/api/v1/tools/life-admin-generator/calculate
- [Repair or Replace](https://repairorreplace.usefulweb.site/): Fix it or buy new? The 50% rule plus a cost-per-year check, with a clear verdict. API: POST https://usefulweb.site/api/v1/tools/repair-or-replace/calculate
- [True Cost Calculator](https://truecostcalculator.usefulweb.site/): What a car, pet, appliance, home or gadget really costs per year, month and day. API: POST https://usefulweb.site/api/v1/tools/true-cost-calculator/calculate
- [Bill Detective](https://billdetective.usefulweb.site/): Spot spikes, price changes and calculation errors across your utility bills. API: POST https://usefulweb.site/api/v1/tools/bill-detective/calculate
- [Break-even Explorer](https://breakevenexplorer.usefulweb.site/): When does an investment pay for itself? Payback, NPV and IRR for solar, EVs, heat pumps… API: POST https://usefulweb.site/api/v1/tools/break-even-explorer/calculate
- [Bulk Buy Brain](https://bulkbuybrain.usefulweb.site/): Is the bulk pack really cheaper once waste, storage and tied-up cash are counted? API: POST https://usefulweb.site/api/v1/tools/bulk-buy-brain/calculate
- [Hidden Fee Finder](https://hiddenfeefinder.usefulweb.site/): Paste a quote, contract or invoice and see every fee, tax, penalty and add-on. API: POST https://usefulweb.site/api/v1/tools/hidden-fee-finder/calculate
- [Inflation Time Machine](https://inflationtimemachine.usefulweb.site/): What was money from one year worth in another? CPI-based, 20 countries, World Bank data. API: POST https://usefulweb.site/api/v1/tools/inflation-time-machine/calculate
- [Price Per Everything](https://pricepereverything.usefulweb.site/): Compare products by price per gram, use, serving, hour or year of life. API: POST https://usefulweb.site/api/v1/tools/price-per-everything/calculate
- [Salary Reality Check](https://salaryrealitycheck.usefulweb.site/): Compare job offers by real net pay per hour, including commute time and living costs. API: POST https://usefulweb.site/api/v1/tools/salary-reality-check/calculate
- [Subscription Stack](https://subscriptionstack.usefulweb.site/): Add up every subscription, spot overlaps and see which ones to cancel and what you save. API: POST https://usefulweb.site/api/v1/tools/subscription-stack/calculate
- [Warranty Value Calculator](https://warrantyvaluecalculator.usefulweb.site/): Is the extended warranty worth it? Expected payout vs. price and break-even failure rate. API: POST https://usefulweb.site/api/v1/tools/warranty-value-calculator/calculate
- [Food Storage Guide](https://foodstorageguide.usefulweb.site/): How long is food safe in the fridge or freezer? Dates from the official FoodSafety.gov chart. API: POST https://usefulweb.site/api/v1/tools/food-storage-guide/calculate
- [Household Maintenance Calendar](https://householdmaintenancecalendar.usefulweb.site/): A dated home maintenance schedule for your appliances and features, as a calendar file. API: POST https://usefulweb.site/api/v1/tools/household-maintenance-calendar/calculate
- [Jet Lag Planner](https://jetlagplanner.usefulweb.site/): A day-by-day sleep, light and caffeine plan to beat jet lag, with calendar export. API: POST https://usefulweb.site/api/v1/tools/jet-lag-planner/calculate
- [Leftover Chef](https://leftoverchef.usefulweb.site/): Turn leftovers and fridge odds and ends into 5 recipe ideas, using what expires first. API: POST https://usefulweb.site/api/v1/tools/leftover-chef/calculate
- [Moving Box Planner](https://movingboxplanner.usefulweb.site/): How many moving boxes, how much tape, which truck and when to start packing. API: POST https://usefulweb.site/api/v1/tools/moving-box-planner/calculate
- [Room Layout Optimizer](https://roomlayoutoptimizer.usefulweb.site/): Auto-arrange furniture in a room around doors, windows and a clear walkway. API: POST https://usefulweb.site/api/v1/tools/room-layout-optimizer/calculate
- [Travel Connection Checker](https://travelconnectionchecker.usefulweb.site/): Estimate your odds of making a flight connection, step by step. API: POST https://usefulweb.site/api/v1/tools/travel-connection-checker/calculate
- [Will It Fit?](https://willitfit.usefulweb.site/): Check if a sofa, wardrobe or box fits through doors, corners, stairs and lifts. API: POST https://usefulweb.site/api/v1/tools/will-it-fit/calculate
- [AI Answer Verifier](https://aianswerverifier.usefulweb.site/): Split an AI answer into claims and see which ones your sources actually support. API: POST https://usefulweb.site/api/v1/tools/ai-answer-verifier/calculate
- [Error Message Translator](https://errormessagetranslator.usefulweb.site/): Paste a technical error and get the plain-English cause and troubleshooting steps. API: POST https://usefulweb.site/api/v1/tools/error-message-translator/calculate
- [File Format Doctor](https://fileformatdoctor.usefulweb.site/): Find out what a file really is from its bytes, why it will not open and how to convert it. API: POST https://usefulweb.site/api/v1/tools/file-format-doctor/calculate
- [Privacy Policy Decoder](https://privacypolicydecoder.usefulweb.site/): What a privacy policy says it collects, shares, sells and keeps — with quoted evidence. API: POST https://usefulweb.site/api/v1/tools/privacy-policy-decoder/calculate
- [Prompt-to-Tool Router](https://prompttotoolrouter.usefulweb.site/): Describe your problem in plain words and get the right tools and order to use them. API: POST https://usefulweb.site/api/v1/tools/prompt-to-tool-router/calculate
- [Scam Signal Checker](https://scamsignalchecker.usefulweb.site/): Check a message or link for common scam and phishing warning signs — without clicking. API: POST https://usefulweb.site/api/v1/tools/scam-signal-checker/calculate
- [Screenshot to Steps](https://screenshottosteps.usefulweb.site/): Turn a screenshot of an app or website into numbered steps for what you want to do. API: POST https://usefulweb.site/api/v1/tools/screenshot-to-steps/calculate
- [Website Change Explainer](https://websitechangeexplainer.usefulweb.site/): Compare two versions of a page and see which changes matter: prices, terms, dates, links. API: POST https://usefulweb.site/api/v1/tools/website-change-explainer/calculate
- [Accessibility Fixer](https://accessibilityfixer.usefulweb.site/): Turn WCAG 2.2 problems in your HTML into concrete code fixes, grouped by effort. API: POST https://usefulweb.site/api/v1/tools/accessibility-fixer/calculate
- [Before You Sign](https://beforeyousign.usefulweb.site/): Spot risky contract clauses (renewal, notice, liability, non-compete…) before you sign. API: POST https://usefulweb.site/api/v1/tools/before-you-sign/calculate
- [Digital Estate Organizer](https://digitalestateorganizer.usefulweb.site/): List your online accounts and get a prioritised plan for what happens to them – no passwords needed. API: POST https://usefulweb.site/api/v1/tools/digital-estate-organizer/calculate
- [Disaster Prep Builder](https://disasterprepbuilder.usefulweb.site/): Build an emergency supply list for your household from official Ready.gov or BBK guidance. API: POST https://usefulweb.site/api/v1/tools/disaster-prep-builder/calculate
- [The Compatibility Engine](https://compatibilityengine.usefulweb.site/): Will this charger, cable, version or PC part work together? Rule-based checks with margins. API: POST https://usefulweb.site/api/v1/tools/compatibility-engine/calculate
- [What Changed in This Law?](https://whatchangedinthislaw.usefulweb.site/): Compare two versions of a law or regulation section by section, with changed numbers and deadlines. API: POST https://usefulweb.site/api/v1/tools/what-changed-in-this-law/calculate
- [Accessibility Snapshot](https://a11ysnapshot.usefulweb.site/): Static WCAG 2.2 snapshot of a page: findings by severity, evidence and manual checks. API: POST https://usefulweb.site/api/v1/tools/a11y-snapshot/calculate
- [CiteShape](https://citeshape.usefulweb.site/): Paste a DOI, ORCID iD, ISBN or arXiv ID: validated, resolved, and formatted as APA, BibTeX and RIS. API: POST https://usefulweb.site/api/v1/tools/citeshape/calculate
- [DataFresh](https://datafresh.usefulweb.site/): Is this dataset or API still fresh? Newest record, update cadence check and schema drift. API: POST https://usefulweb.site/api/v1/tools/datafresh/calculate
- [FileFit](https://filefit.usefulweb.site/): Can this app open, edit or convert that file format? Verified facts with sources. API: POST https://usefulweb.site/api/v1/tools/filefit/calculate
- [LocaleKit Country Format Rules](https://localekit.usefulweb.site/): Address form fields, postal-code regex, calling code and date formats for any country. API: POST https://usefulweb.site/api/v1/tools/localekit/calculate
- [RuleDate Deadline Calculator](https://ruledate.usefulweb.site/): Business-day and deadline maths with public holidays and a step-by-step rule trace. API: POST https://usefulweb.site/api/v1/tools/ruledate/calculate
- [TimeFair Meeting Planner](https://timefair.usefulweb.site/): Find fair meeting times across time zones, with DST-exact local times and rotation. API: POST https://usefulweb.site/api/v1/tools/timefair/calculate
- [UnitProof Unit Calculator](https://unitproof.usefulweb.site/): Unit maths you can audit: dimension check, exact factors and a full derivation tree. API: POST https://usefulweb.site/api/v1/tools/unitproof/calculate
- [Account Abstraction Explorer](https://accountabstractionexplorer.usefulweb.site/): Decode ERC-4337 bundles: UserOperations, paymasters, gas per op, deployed smart accounts. API: POST https://usefulweb.site/api/v1/tools/account-abstraction-explorer/calculate
- [Blockchain Incident Replay](https://blockchainincidentreplay.usefulweb.site/): Replay an exploit from tx hashes: ordered timeline, fund-flow graph and who profited. API: POST https://usefulweb.site/api/v1/tools/blockchain-incident-replay/calculate
- [Bridge Transfer Tracker](https://bridgetransfertracker.usefulweb.site/): Where is my bridged money? Finds the bridge deposit in a transaction and checks if it arrived. API: POST https://usefulweb.site/api/v1/tools/bridge-transfer-tracker/calculate
- [Cross-Chain Transaction Explorer](https://crosschaintransactionexplorer.usefulweb.site/): Follow one transaction across chains: source tx, bridge deposit and destination fill on a timeline. API: POST https://usefulweb.site/api/v1/tools/cross-chain-transaction-explorer/calculate
- [DAO Governance Explorer](https://daogovernanceexplorer.usefulweb.site/): Snapshot proposals, vote concentration, Governor state and treasury balances in one view. API: POST https://usefulweb.site/api/v1/tools/dao-governance-explorer/calculate
- [DeFi Liquidation Explorer](https://defiliquidationexplorer.usefulweb.site/): Recent Aave V3 liquidations in USD, who liquidated whom, and a live health-factor check. API: POST https://usefulweb.site/api/v1/tools/defi-liquidation-explorer/calculate
- [Gas Fee Intelligence Explorer](https://gasfeeintelligenceexplorer.usefulweb.site/): Live gas on 7 EVM chains: base fee, tips, trend and the USD cost of transfers and swaps. API: POST https://usefulweb.site/api/v1/tools/gas-fee-intelligence-explorer/calculate
- [MEV Explorer](https://mevexplorer.usefulweb.site/): Who extracted value in this block? Sandwiches, arbitrage, liquidations, builder and tips. API: POST https://usefulweb.site/api/v1/tools/mev-explorer/calculate
- [Rollup Batch Explorer](https://rollupbatchexplorer.usefulweb.site/): How L2 transactions reach Ethereum: unsafe → safe → finalized, blobs, batch costs, withdrawal waits. API: POST https://usefulweb.site/api/v1/tools/rollup-batch-explorer/calculate
- [Smart Contract Relationship Graph](https://smartcontractrelationshipgraph.usefulweb.site/): Map a contract's proxy, implementation, admin, owner, deployer/factory and token links as a graph. API: POST https://usefulweb.site/api/v1/tools/smart-contract-relationship-graph/calculate
- [Smart Contract Upgrade Explorer](https://contractupgradeexplorer.usefulweb.site/): Is this smart contract upgradeable, who controls upgrades, and what changed? API: POST https://usefulweb.site/api/v1/tools/contract-upgrade-explorer/calculate
- [Stablecoin Flow Explorer](https://stablecoinflowexplorer.usefulweb.site/): USDC/USDT supply per chain, recent mints, burns and whale transfers, cross-chain totals. API: POST https://usefulweb.site/api/v1/tools/stablecoin-flow-explorer/calculate
- [Token Unlock Explorer](https://tokenunlockexplorer.usefulweb.site/): Model token vesting (cliff, linear, monthly, tranches, TGE) or audit a VestingWallet. API: POST https://usefulweb.site/api/v1/tools/token-unlock-explorer/calculate
- [Transaction Decoder](https://transactiondecoder.usefulweb.site/): See what an EVM transaction actually did: call, events, token transfers, fee, finality. API: POST https://usefulweb.site/api/v1/tools/transaction-decoder/calculate
- [Wallet Permission Explorer](https://walletpermissionexplorer.usefulweb.site/): Who can move your tokens? Allowances, Permit2, NFT operators and EIP-7702 delegation, with risk. API: POST https://usefulweb.site/api/v1/tools/wallet-permission-explorer/calculate
- [ASN Relationship Explorer](https://asnrelationshipexplorer.usefulweb.site/): An autonomous system at a glance: holder, country, BGP neighbours and announced prefixes. API: POST https://usefulweb.site/api/v1/tools/asn-relationship-explorer/calculate
- [BGP Route Explorer](https://bgprouteexplorer.usefulweb.site/): Who announces an IP or prefix in BGP: origin ASes, RPKI validity, visibility and origin changes. API: POST https://usefulweb.site/api/v1/tools/bgp-route-explorer/calculate
- [CDN Behaviour Explorer](https://cdnbehaviorexplorer.usefulweb.site/): Which CDN serves a URL, whether it caches it (HIT/MISS, Age, TTL) and how, from two requests. API: POST https://usefulweb.site/api/v1/tools/cdn-behavior-explorer/calculate
- [Certificate Transparency Explorer](https://certificatetransparencyexplorer.usefulweb.site/): Every logged certificate for a domain: history, issuers, subdomains, wildcards and expiry. API: POST https://usefulweb.site/api/v1/tools/certificate-transparency-explorer/calculate
- [DNS + Certificate Explorer](https://dnscertificateexplorer.usefulweb.site/): DNS records, e-mail security, CAA, live TLS certificate and CT history for a domain. API: POST https://usefulweb.site/api/v1/tools/dns-certificate-explorer/calculate
- [Domain History Graph](https://domainhistorygraph.usefulweb.site/): Registration, DNS, hosting networks, certificates and Wayback captures of a domain as a timeline. API: POST https://usefulweb.site/api/v1/tools/domain-history-graph/calculate
- [E-mail Infrastructure Explorer](https://emailinfrastructureexplorer.usefulweb.site/): MX, SPF lookups, DMARC, DKIM, MTA-STS, TLS-RPT and BIMI for a domain, scored with fixes. API: POST https://usefulweb.site/api/v1/tools/email-infrastructure-explorer/calculate
- [Global DNS Explorer](https://globaldnsexplorer.usefulweb.site/): Ask every authoritative name server and public resolvers: records, propagation, DNSSEC, mistakes. API: POST https://usefulweb.site/api/v1/tools/global-dns-explorer/calculate
- [HTTP Technology Explorer](https://httptechnologyexplorer.usefulweb.site/): Headers, compression, caching, HTTP/2-3 hints, redirects, security and tech stack for a URL. API: POST https://usefulweb.site/api/v1/tools/http-technology-explorer/calculate
- [Internet Outage Atlas](https://internetoutageatlas.usefulweb.site/): Correlate public outage signals (IODA, RIPEstat BGP, live probe) for a country, ASN or domain. API: POST https://usefulweb.site/api/v1/tools/internet-outage-atlas/calculate
- [IPv6 Readiness Explorer](https://ipv6readinessexplorer.usefulweb.site/): Is a domain reachable over IPv6? Web, DNS and mail checks, address classes and a scored report. API: POST https://usefulweb.site/api/v1/tools/ipv6-readiness-explorer/calculate
- [Artifact Provenance Explorer](https://artifactprovenanceexplorer.usefulweb.site/): Verify npm build provenance: Sigstore signature, transparency log, source repo and commit. API: POST https://usefulweb.site/api/v1/tools/artifact-provenance-explorer/calculate
- [Container Image Explorer](https://containerimageexplorer.usefulweb.site/): Inspect a container image: platforms, layers, base image, root user, labels and cosign signature. API: POST https://usefulweb.site/api/v1/tools/container-image-explorer/calculate
- [CVE Relationship Graph](https://cverelationshipgraph.usefulweb.site/): One CVE or GHSA as a graph: aliases, affected packages, fixed versions, KEV status and EPSS. API: POST https://usefulweb.site/api/v1/tools/cve-relationship-graph/calculate
- [Dependency Vulnerability Explorer](https://dependencyvulnerabilityexplorer.usefulweb.site/): Known vulnerabilities in your dependencies, and the version that fixes each one. API: POST https://usefulweb.site/api/v1/tools/dependency-vulnerability-explorer/calculate
- [OAuth Permission Explorer](https://oauthpermissionexplorer.usefulweb.site/): What an OAuth consent request really allows: scopes, risky combinations and flow problems. API: POST https://usefulweb.site/api/v1/tools/oauth-permission-explorer/calculate
- [Open Source Trust Explorer](https://opensourcetrustexplorer.usefulweb.site/): Is this open-source project maintained and trustworthy? Scorecard, activity and provenance. API: POST https://usefulweb.site/api/v1/tools/open-source-trust-explorer/calculate
- [Package Ecosystem Graph](https://packageecosystemgraph.usefulweb.site/): Who depends on what: resolved dependency graph, duplicates and the blast radius of breaking changes. API: POST https://usefulweb.site/api/v1/tools/package-ecosystem-graph/calculate
- [SBOM Explorer](https://sbomexplorer.usefulweb.site/): Open a CycloneDX or SPDX SBOM: components, licences, dependency tree and known vulnerabilities. API: POST https://usefulweb.site/api/v1/tools/sbom-explorer/calculate
- [Security Advisory Timeline](https://securityadvisorytimeline.usefulweb.site/): Disclosures, affected ranges, fixes and withdrawals for a package on one timeline, with time-to-fix. API: POST https://usefulweb.site/api/v1/tools/security-advisory-timeline/calculate
- [Security Configuration Scanner](https://securityconfigurationscanner.usefulweb.site/): Passive, graded check of a domain's TLS, security headers, DNS security and security.txt. API: POST https://usefulweb.site/api/v1/tools/security-configuration-scanner/calculate
- [API Explorer of Explorers](https://apiexplorerofexplorers.usefulweb.site/): Search 2,500+ public APIs or summarise any OpenAPI spec: servers, auth, endpoints, changes. API: POST https://usefulweb.site/api/v1/tools/api-explorer-of-explorers/calculate
- [CI/CD Failure Explorer](https://cicdfailureexplorer.usefulweb.site/): Paste CI logs from several runs: root cause per run, grouped signatures, top causes and fixes. API: POST https://usefulweb.site/api/v1/tools/cicd-failure-explorer/calculate
- [Cron Job Explorer](https://cronjobexplorer.usefulweb.site/): Paste a crontab or CronJob YAML: plain-English schedules, DST-exact next runs, herds and overlaps. API: POST https://usefulweb.site/api/v1/tools/cron-job-explorer/calculate
- [Data Lineage Explorer](https://datalineageexplorer.usefulweb.site/): Paste SQL or dbt models: table lineage graph, column lineage and upstream/downstream of any field. API: POST https://usefulweb.site/api/v1/tools/data-lineage-explorer/calculate
- [Distributed Trace Explorer](https://distributedtraceexplorer.usefulweb.site/): Paste an OTLP, Jaeger or Zipkin trace: span tree, critical path, self-time, N+1 calls and errors. API: POST https://usefulweb.site/api/v1/tools/distributed-trace-explorer/calculate
- [Kubernetes Event Explorer](https://kuberneteseventexplorer.usefulweb.site/): Paste kubectl events and get a timeline, reason taxonomy and likely root causes per workload. API: POST https://usefulweb.site/api/v1/tools/kubernetes-event-explorer/calculate
- [OpenAPI Diff Explorer](https://openapidiffexplorer.usefulweb.site/): Compare two versions of an OpenAPI spec and see exactly which changes break clients. API: POST https://usefulweb.site/api/v1/tools/openapi-diff-explorer/calculate
- [Query Plan Visualizer](https://queryplanvisualizer.usefulweb.site/): PostgreSQL EXPLAIN (ANALYZE) or MySQL EXPLAIN JSON → plan tree, hot nodes and index suggestions. API: POST https://usefulweb.site/api/v1/tools/query-plan-visualizer/calculate
- [Serverless Performance Explorer](https://serverlessperformanceexplorer.usefulweb.site/): Lambda REPORT lines → cold-start rate, p50/p95/p99, memory right-sizing and cost per 1M calls. API: POST https://usefulweb.site/api/v1/tools/serverless-performance-explorer/calculate
- [Terraform Plan & Drift Explorer](https://terraformdriftexplorer.usefulweb.site/): Paste terraform show -json: drift, replacement reasons, attribute diffs and risky deletes. API: POST https://usefulweb.site/api/v1/tools/terraform-drift-explorer/calculate
- [Agent Permission Graph](https://agentpermissiongraph.usefulweb.site/): See what your AI agent can reach: MCP servers, commands, files, network and secrets – with risks. API: POST https://usefulweb.site/api/v1/tools/agent-permission-graph/calculate
- [AI Agent Tool Explorer](https://aiagenttoolexplorer.usefulweb.site/): Index of tools AI agents can call: this site, the MCP Registry or your definitions, by capability. API: POST https://usefulweb.site/api/v1/tools/ai-agent-tool-explorer/calculate
- [AI Model Compatibility Explorer](https://aimodelcompatibilityexplorer.usefulweb.site/): Which LLMs take images, audio or files, fit your context and support tools or structured outputs? API: POST https://usefulweb.site/api/v1/tools/ai-model-compatibility-explorer/calculate
- [AI Tool-Call Trace Explorer](https://toolcalltraceexplorer.usefulweb.site/): Paste an agent transcript: see every tool call in order, with errors, timings, retries and loops. API: POST https://usefulweb.site/api/v1/tools/tool-call-trace-explorer/calculate
- [AI Website Readiness Explorer](https://aiwebsitereadinessexplorer.usefulweb.site/): Can ChatGPT, Claude, Perplexity and AI agents read your website? Explainable score. API: POST https://usefulweb.site/api/v1/tools/ai-website-readiness-explorer/calculate
- [LLM Cost Explorer](https://llmcostexplorer.usefulweb.site/): Monthly LLM API cost per model for your workload, with prompt-caching and batch savings. API: POST https://usefulweb.site/api/v1/tools/llm-cost-explorer/calculate
- [MCP Server Explorer](https://mcpserverexplorer.usefulweb.site/): Inspect any MCP server before you connect an AI agent: tools, permissions, risks, changes over time. API: POST https://usefulweb.site/api/v1/tools/mcp-server-explorer/calculate
- [Model Behavior Regression Explorer](https://modelbehaviorregressionexplorer.usefulweb.site/): Compare eval results of two model versions: accuracy, regressions, McNemar p-value, flaky items. API: POST https://usefulweb.site/api/v1/tools/model-behavior-regression-explorer/calculate
- [RAG Citation Debugger](https://ragcitationdebugger.usefulweb.site/): Check a RAG answer's citations against the retrieved chunks: uncited claims, wrong sources, numbers. API: POST https://usefulweb.site/api/v1/tools/rag-citation-debugger/calculate
- [Structured Output Validator](https://structuredoutputvalidator.usefulweb.site/): Validate AI JSON output against a JSON Schema: parse errors with line/column, plain-language fixes. API: POST https://usefulweb.site/api/v1/tools/structured-output-validator/calculate
- [Energy Grid Explorer](https://energygridexplorer.usefulweb.site/): Generation mix, load, renewable share, cross-border flows and power prices for European grids. API: POST https://usefulweb.site/api/v1/tools/energy-grid-explorer/calculate
- [Internet Archive Change Explorer](https://internetarchivechangeexplorer.usefulweb.site/): See how a web page changed in the Wayback Machine: capture timeline plus the changes that matter. API: POST https://usefulweb.site/api/v1/tools/internet-archive-change-explorer/calculate
- [Public Spending Explorer](https://publicspendingexplorer.usefulweb.site/): Search government contracts and grants: who pays whom, totals per agency and vendor. API: POST https://usefulweb.site/api/v1/tools/public-spending-explorer/calculate
- [Satellite Change Explorer](https://satellitechangeexplorer.usefulweb.site/): Compare NASA satellite images of any place on two dates: true colour, NDVI, night lights. API: POST https://usefulweb.site/api/v1/tools/satellite-change-explorer/calculate
- [Software Adoption Explorer](https://softwareadoptionexplorer.usefulweb.site/): Open-source usage signals: weekly downloads, growth and version adoption for npm, PyPI, crates. API: POST https://usefulweb.site/api/v1/tools/software-adoption-explorer/calculate
- [Explorer of Everything](https://explore.usefulweb.site/): Search transactions, contracts, domains, packages, advisories, MCP servers and websites in one box. API: POST https://usefulweb.site/api/v1/tools/explore/calculate

## Workflows
- [Moving home](https://usefulweb.site/workflows/moving-home): Personalised moving checklist with deadlines, box and van estimate, an optional "will the sofa fit?" check, and a maintenance calendar for the new place. Steps: life-admin-generator → moving-box-planner → will-it-fit → household-maintenance-calendar. API: POST https://usefulweb.site/api/v1/workflows/moving-home/run
- [Is this message a scam?](https://usefulweb.site/workflows/suspicious-message): Analyses a suspicious e-mail/SMS for scam signals, then checks the reachability and security headers of the linked website. Never claims a message is safe. Steps: scam-signal-checker → headerlens. API: POST https://usefulweb.site/api/v1/workflows/suspicious-message/run
- [Subscription clean-up](https://usefulweb.site/workflows/subscription-cleanup): Totals your subscriptions, flags overlaps and poor value, and gives verified cancellation steps for the one you want to cancel first. Steps: subscription-stack → cancellation-navigator. API: POST https://usefulweb.site/api/v1/workflows/subscription-cleanup/run