Private tools.
Built for developers.
22 free developer tools that run entirely in your browser. Your tokens, payloads, and API data never leave your machine. No login, no ads, no tracking.
Everything in your stack
Hand-picked utilities covering the full development lifecycle — from API design to deployment checks.
REST Client
Send HTTP requests, inspect headers, and test endpoints right in your browser. All methods supported.
Try it free → — REST ClientJSON Transformer
Format, minify, and convert JSON to YAML or CSV instantly with syntax highlighting.
Try it free → — JSON TransformerRegex Studio
Build and test regex patterns live with named groups, flags, match highlighting, and 10 one-click common pattern presets.
Try it free → — Regex TesterJWT Debugger
Decode and inspect JSON Web Tokens — header, payload, claims, and expiry.
Try it free → — JWT DebuggerCron Builder
Visual cron expression editor with human-readable output and next run times.
Try it free → — Cron BuilderData Format Converter
Convert between JSON, YAML, TOML, and CSV instantly in your browser.
Try it free → — Data Format ConverterSQL Formatter
Format and beautify SQL for Postgres, MySQL, SQLite, and BigQuery.
Try it free → — SQL FormatterURL Inspector
Parse any URL into its components, inspect query params, encode and decode strings.
Try it free → — URL ParserBase64 / Hash
Encode, decode, and hash strings with MD5, SHA-1, SHA-256, SHA-384, SHA-512, and HMAC.
Try it free → — Base64 EncoderWebSocket Tester
Connect to WebSocket servers, send messages, and inspect frames in real time.
Try it free → — WebSocket TesterDiff Tool
Compare two blocks of text line by line with character-level inline highlighting of exact changes.
Try it free → — Diff CheckerTimestamp Converter
Convert Unix timestamps across 15 timezones. Duration calculator, timezone converter, and batch convert included.
Try it free → — Timestamp ConverterHTML Formatter
Format and beautify HTML with proper indentation and syntax highlighting.
Try it free → — HTML FormatterColor Converter
Convert between HEX, RGB, HSL, and OKLCH instantly. Pick colors visually.
Try it free → — Color ConverterUUID Generator
Generate UUIDs v1, v4, and v7 in bulk. Copy to clipboard with one click.
Try it free → — UUID GeneratorNumber Base Converter
Convert between binary, octal, decimal, and hex instantly.
Try it free → — Number Base ConverterImage Converter
Convert SVG to PNG, resize images, and export to WebP. Quality control, aspect lock, live preview.
Try it free → — Image ConverterPassword Generator
Generate strong passwords with entropy meter, bulk mode, passphrase mode, and custom character sets.
Try it free → — Password GeneratorMarkdown Previewer
Write and preview Markdown live. GFM tables, task lists, code blocks. Export as HTML.
Try it free → — Markdown PreviewerJWT Builder
Build and sign JWT tokens with custom headers, payloads, and HS256 signing. Preview the encoded token instantly.
Try it free → — JWT BuilderCSV Editor
Paste or drop a CSV file to get an interactive table. Sort, filter, and convert to JSON or TSV in one click.
Try it free → — CSV EditorHTTP Headers Inspector
Paste HTTP response headers and get instant security, caching, and performance analysis with explanations.
Try it free → — HTTP Headers InspectorWhat's next?
New tools are added regularly. Check the roadmap to see what's in the pipeline and what's already shipped.
View roadmap → FeedbackGot an idea?
If there's a tool you wish existed here, I want to hear it. Every suggestion gets read personally.
Send a suggestion →Built by devs,
for devs.
No bloat. No dark patterns. Every tool is designed to get out of your way and let you ship.
Runs locally in your browser
Tool inputs are processed on your machine. Your tokens, payloads, and queries are never sent to DevCrate servers.
Fast, focused workflows
Open a tool and get the job done — no accounts, no installs, no ad clutter, no dark patterns.
Useful free tier
Every live tool is free with clear usage limits. No bait-and-switch. Upgrade when you need more.
Built in public
Public roadmap, direct access to the builder, and updates shared openly as they ship.
$ devcrate jwt decode --token
eyJhbGciOiJSUzI1NiJ9...
✓ Header
alg: RS256
typ: JWT
✓ Payload
sub: "user_9kx3p"
iat: 1742549200
exp: 1742552800 ✓ valid
scope: "read write"
✓ Signature verified via JWKS
$
Simple, honest pricing.
All 22 live tools are free to start. Upgrade for higher usage limits today, with additional Pro features rolling out on the public roadmap. No surprise charges, no dark patterns.
- All 22 developer tools
- REST Client — 10 requests/day
- WebSocket — 50 messages/day
- Batch timestamps — 50 per run
- SQL / JSON / Diff / HTML — 50KB input
- Regex — 25KB test strings
- Browser-based & offline-first
- Light / dark theme toggle
- Community support
First month free — use EARLYBIRD10
- Everything in Free
- REST Client — 100 requests/day NOW
- WebSocket — 500 messages/day NOW
- Batch timestamps — unlimited
- SQL / JSON / Diff / HTML — 500KB input
- Regex — 100KB test strings
- HMAC generator (SHA-256/384/512)
- Export results as files NOW
- Session history — last 50 inputs NOW
- Save named configurations NOW
- Priority email support
- Early access to new tools
- Everything in Pro
- REST Client — unlimited requests
- WebSocket — unlimited messages
- All tools — unlimited input
- Unlimited saved configurations
- User accounts & cloud sync (Q3 2026)
- Shareable tool links (Q3 2026)
- Collections (Q3 2026)
- Team workspaces (Q3 2026) planned
- CLI & API access (Q4 2026)
- Priority support
Common questions
Ship faster, starting now.
Stop switching between tabs and half-baked tools. Everything you need, in one place, free to start.