Development
An in-browser GraphQL client: write queries and variables, send them to any GraphQL endpoint, and inspect formatted JSON results or error arrays — perfect for iterating on schemas during development
graphql-playgroundDevelopment
A lightweight in-browser HTTP client (mini Postman): send GET/POST/PUT/DELETE requests with custom headers and body, inspect status, headers, timing, and formatted response — all from your browser
http-request-testerNetwork
Visualize the geographic location, network (ASN/ISP), timezone, and security posture of any IP address as a rich card report
ip-geolocationDevelopment
A searchable, localized cheat sheet for regular expression syntax — character classes, anchors, quantifiers, groups & references, lookarounds, escape sequences, and flags — with a built-in quick tester
regex-cheat-sheetDevelopment
Step through how a regular expression matches a string position by position: visualize match attempts, partial successes, backtracks, and captures — a learning tool for understanding regex behavior, not just the final result
regex-debuggerDevelopment
Connect to any WebSocket (ws:// or wss://) endpoint from your browser, send and receive messages, and inspect open/close/error events with codes — ideal for debugging real-time APIs and sockets
websocket-testerDevelopment
Statically check Markdown links for format errors, broken anchors, and undefined references (no network requests)
markdown-link-checkerDevelopment
Check Markdown for style issues: heading levels, code fences, list consistency, and more (zero-dependency rule engine)
markdown-linterDevelopment
Convert between natural-language durations and ISO 8601 durations (PnYnMnDTnHnMnS) in both directions with validation of edge cases
iso-8601-duration-builderDevelopment
Render a regular expression as an SVG railroad (syntax) diagram showing literals, groups, alternations, and repetition, with capture-group numbering and flag explanations
regex-railroad-diagram-visualizerDevelopment
Upload any binary file and inspect it as a classic hex dump with offset, hex bytes, and ASCII columns (read-only)
hex-editorDevelopment
Complete HTTP status code reference (1xx–5xx) with semantics, typical scenarios, and retry advice in a filterable comparison table
http-status-reference