Developers
Every utility a developer reaches for daily — in one tab.
Start here
55 tools curated for youProductivity
Calculators
Spreadsheets
Media
Location
Daily Essentials
Schools
Toolenza for Developers
The toolbelt without the tabs
A working developer day involves a dozen tiny tools that don't deserve their own apps: paste a JWT to see what's inside it, expand a cron expression to verify it fires on the right day, escape some HTML, generate a UUID, diff two JSON payloads, mock a CSV. Most engineers keep five sites open and lose half of them every reboot.
Toolenza puts every one of those tools behind a single URL pattern (/tools/{slug}) and a single keyboard shortcut (⌘K). Nothing in the browser-only tools ever uploads — your tokens, payloads, and configs never leave your machine. The dev-facing tools that do call out (geocoders, currency, AI) say so on the page before you submit.
What developers actually open every week
json— format / minify / validate / diff JSON. Useful for response inspection and API debugging.regex— live tester with named-group highlighting and a /pattern/ flag editor.jwt— decode (and verify, given a secret) JSON Web Tokens — header, payload, signature.cron— translate0 */6 * * 1-5into English ("every 6 hours, Monday to Friday") and show the next 5 fire times.base64— encode/decode, file ↔ data URL, image ↔ base64.hash/hmac— MD5, SHA-1, SHA-256, SHA-512; raw + HMAC modes.uuid— v1 (timestamp), v4 (random), v7 (sortable). Bulk generation supported.developer-calculator— programmer-mode calc: hex/dec/oct/bin views, bitwise ops, shifts.utm-builder— for the marketing links your PM keeps pasting in Slack.color+contrast-checker— pick palettes and verify WCAG AA/AAA contrast for accessibility audits.og-image-generator+meta-tag-preview— final-mile SEO and social previews.favicon-generator— generate every platform's icon sizes from one square PNG.
Why the Cmd-K palette matters
As the catalog grows, finding tools by browsing breaks. Toolenza ships a global ⌘K / Ctrl+K palette mounted on every page. Type three letters, hit enter — recently-used tools float to the top. Recent tools are stored in your browser, so the palette adapts to your workflow without telemetry.
The AI Brain (⌘⇧K) goes one step further: describe a task in plain English ("split this PDF every 5 pages," "format this SQL," "give me a regex for ISO 8601 dates") and it routes you to the right tool with the arguments pre-filled.
Frequently asked questions
For ~90% of the catalog, no — JSON/regex/JWT/base64/hash/UUID/cron/diff and all the cryptography tools run entirely in your browser. The exceptions are tools that genuinely need a server: PDF compress/protect/unlock (Ghostscript/qpdf), AI-backed actions, geocoders, and live currency rates. Each tool says so on the page before you submit anything.
Yes — Toolenza exposes a v1 REST API at `/api/v1/*` with bearer-token auth and per-plan rate limits (1k/mo free, up to 5M/mo on Scale). Endpoints include JSON format/validate, unit conversion, currency conversion, geocoding, QR generation. See `/developers` for the full schema.
Not directly today. The palette indexes the public catalog. We're considering a `/tools/local` extension point that lets the browser extension surface local CLI commands; open an issue if you want it.
PDF uploads (compress/protect/unlock) live on disk only for the duration of the request and are deleted as soon as your download starts. AI calls stream through OpenAI server-side and we don't persist prompts or responses. The geocoder forwards to Google Maps / Mapbox and is rate-limited per IP.