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Developer tools for AI engineering
Calculators, analyzers, and utilities for building with LLMs. Everything runs in your browser — no signup, and your data never leaves your machine.
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Calculators, analyzers, and utilities for building with LLMs. Everything runs in your browser — no signup, and your data never leaves your machine.
Decode and verify JWTs entirely in your browser — your token never touches a server.
Engineering UtilitiesConvert between JSON, YAML and TOML with instant validation and clear error lines.
Engineering UtilitiesBuild cron expressions visually or paste one to get plain English and next run times.
Engineering UtilitiesGenerate UUIDv4, sortable UUIDv7, ULIDs and NanoIDs with format anatomy explained.
Engineering UtilitiesDebug HMAC webhook signatures locally — Stripe, GitHub and generic SHA-256 presets.
Engineering UtilitiesTest regular expressions with live highlighting and a plain-English pattern breakdown.
Engineering UtilitiesCompare text or JSON semantically — word-level highlights, fully in your browser.
Engineering UtilitiesPing major AI provider endpoints from your browser and compare response times live.
Engineering UtilitiesWill that model fit on your GPU? VRAM needs by parameter count, quantization and context.
Engineering UtilitiesScan code for leaked API keys, tokens and credentials — entirely in your browser.
Engineering UtilitiesPaste a curl command for any AI API and get Python, TypeScript and Go SDK code.
Engineering UtilitiesEncode and decode Base64, Base64url, URL and hex — instant, private, bidirectional.
Engineering UtilitiesConvert epoch timestamps to human dates across timezones, with a live now ticker.
Engineering UtilitiesEvery HTTP status code explained, with AI-API-specific notes on 429s, 529s and timeouts.
Engineering UtilitiesSHA-256, SHA-512 and MD5 for text or files — computed locally with WebCrypto.
Engineering UtilitiesEntropy bits and realistic crack-time estimates — your password never leaves the page.
Engineering UtilitiesDecompose any URL into parts with a query-parameter table and encoding diagnostics.
Engineering UtilitiesRun JSONPath queries against pasted JSON with live results and syntax help.
Engineering UtilitiesPaste CSV or TSV and get a clean, aligned markdown table — with alignment controls.
Engineering UtilitiesIdentify any AI vendor key by its prefix — sk-ant, ghp, AKIA — with security notes.
Engineering UtilitiesSymbolic to octal permissions and back, with a visual permission grid and presets.
Engineering UtilitiesIs that user agent an AI crawler? GPTBot, ClaudeBot and friends — plus robots.txt rules.
Engineering UtilitiesWCAG AA and AAA contrast checking with fix suggestions — for accessible interfaces.
Engineering UtilitiesHeuristic best-practice checks: layer order, cache busting, root user, image size.
96 tools live · across 5 categories — all free, all client-side.