Free Online Tools for Developers
Fast, private, no sign-up. Every tool runs 100% in your browser — your data never leaves your device.
Unix Timestamp Converter
Convert epoch timestamps to readable dates and back, with automatic seconds/milliseconds detection.
Base64 Encode / Decode
Encode text to Base64 or decode it back instantly. Unicode-safe, works fully offline in your browser.
Hex to RGB Converter
Convert hex color codes to RGB with a live preview, plus RGB-to-hex and CSS-ready output.
UUID Generator
Generate random v4 or time-ordered v7 UUIDs in bulk, with formatting options and one-click copy.
Rem to PX Converter
Convert between rem and px with a custom root font-size, plus a handy reference table.
HTML Entity Encoder / Decoder
Escape & < > " to HTML entities for safe display, or decode entities back to text.
URL Encoder / Decoder
Percent-encode full URLs or just query parameter values, with live decode and one-click copy.
Chmod Calculator
Convert between octal (755), symbolic (rwxr-xr-x) and rwx bits with presets for 644, 755 and 600.
Cron Expression Generator
Build cron schedules visually, read them in plain English, and preview the next 5 run times.
YAML ↔ JSON Converter
Convert YAML to JSON and back with a hand-rolled parser and precise line-numbered errors.
Hash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text, computed live in your browser.
JSON to CSV Converter
Flatten nested JSON arrays to RFC 4180 CSV with a column picker and one-click download.
SVG to Data URI Converter
Turn SVG code into optimized data URIs with live preview and byte-size comparison.
CSS clamp() Calculator
Generate fluid clamp() typography formulas with a live viewport-width slider preview.
HTTP Status Code Lookup
Search 50+ HTTP status codes — what each means and the real-world scenarios behind them.
Binary to Text Converter
Decode binary code to readable text and back. Handles spaces, 0b prefixes and UTF-8 — in your browser.
JSON to SQL Converter
Turn JSON arrays into SQL INSERT statements with auto CREATE TABLE. MySQL, PostgreSQL, SQLite.
XML to JSON Converter
Convert XML to clean JSON instantly. Preserves attributes, groups repeated tags, tames namespaces.
Morse Code Translator
Translate text to Morse code and back — with audio playback, SOS generator and full ITU reference.
ULID Generator
Generate time-ordered, URL-safe ULIDs in bulk — sortable by creation time, plus a ULID timestamp decoder.
CSS Specificity Calculator
Score any CSS selector as (a, b, c) with a per-part breakdown — handles :is(), :not(), :has(), :where().
cURL to Fetch Converter
Turn cURL commands into JavaScript fetch() code — parsed 100% in your browser, safe for API keys.
JSON to TypeScript Converter
Paste JSON and get TypeScript interfaces — nested types, unions, and optional fields inferred automatically.
JSON Schema Generator
Turn any sample JSON into a valid JSON Schema (Draft 2020-12 / Draft-07) — type inference, format detection, required fields.
JWT Decoder
Decode and inspect JSON Web Tokens instantly — header, claims, expiry status. 100% client-side, nothing uploaded.
Caesar Cipher Encoder & Decoder
Encode secret messages or brute-force all 25 shifts to crack one — the classic substitution cipher, free online.
CSS Cubic Bezier Generator
Design custom cubic-bezier() easing curves visually — drag handles, live animation preview, copy-ready CSS.
Why TinyKit?
- Private by design. All conversions happen locally in your browser with JavaScript. Nothing you type is uploaded anywhere — paste secrets, tokens, or proprietary text with confidence.
- Fast and free. No accounts, no paywalls, no waiting. Pages are plain HTML with no heavy frameworks, so they load instantly even on slow connections.
- Built for real workflows. Each tool handles the edge cases developers actually hit: millisecond vs second timestamps, Unicode in Base64, UUID v7, custom root font sizes.