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HOME/DEVELOPER TOOLS

CATEGORY

Developer Tools

Free developer tools: JSON formatter, regex tester, JWT decoder, CSV to JSON converter, URL shortener, Base64, URL encoder, UUID and hash generators.

Developer tools earn trust by being exact: a JSON parser that shows the precise error position, a cron builder that makes the day-of-week logic explicit, encoders that explain the difference between encoding and encryption. This is the toolkit for the daily 1% of the job that is not writing code.

Everything runs client-side — paste real payloads without pasting them into a stranger's server.

JSON Formatter — before
JSON Formatter — after
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AFTERBEFORE
01READY

JSON Formatter

Format, validate and beautify JSON data with syntax highlighting.

Base64 Encoder / Decoder — before
Base64 Encoder / Decoder — after
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AFTERBEFORE
02READY

Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 back to plain text.

URL Encoder / Decoder — before
URL Encoder / Decoder — after
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AFTERBEFORE
03READY

URL Encoder / Decoder

Encode or decode URLs and query strings (percent-encoding).

UUID Generator — before
UUID Generator — after
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AFTERBEFORE
04READY

UUID Generator

Generate random UUIDs (v4) — one or bulk. Copy with one click.

Hash Generator — before
Hash Generator — after
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AFTERBEFORE
05READY

Hash Generator

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text.

Password Strength Checker — before
Password Strength Checker — after
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AFTERBEFORE
06READY

Password Strength Checker

Check how strong your password is: score from very weak to strong, entropy estimate and 6 security checks, 100% local.

Regex Tester — before
Regex Tester — after
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AFTERBEFORE
07READY

Regex Tester

Test JavaScript regular expressions with live matches, capture groups and flags.

JWT Decoder — before
JWT Decoder — after
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AFTERBEFORE
08READY

JWT Decoder

Decode JSON Web Tokens (JWT) instantly: read header, payload and claims as readable JSON. Runs in your browser.

CSV ⇄ JSON Converter — before
CSV ⇄ JSON Converter — after
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AFTERBEFORE
09READY

CSV ⇄ JSON Converter

Convert CSV to JSON and JSON to CSV instantly. Custom delimiters, header-row detection, copy or download.

Fake Data Generator — before
Fake Data Generator — after
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AFTERBEFORE
10READY

Fake Data Generator

Generate realistic fake data: names, emails, phones, addresses, companies, dates, UUIDs and SSNs. Export as CSV.

URL Shortener — before
URL Shortener — after
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AFTERBEFORE
11READY

URL Shortener

Turn any long link into a short, shareable URL in seconds. Copy with one click and session history.

Cron Generator — before
Cron Generator — after
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AFTERBEFORE
12READY

Cron Generator

Build 5-field cron expressions visually with presets and a human-readable description. Compatible with Linux, AWS and GitHub Actions.

Markdown to HTML — before
Markdown to HTML — after
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AFTERBEFORE
13READY

Markdown to HTML

Convert Markdown to clean HTML instantly with a live preview. Headings, lists, links, code blocks and more.

CSS Gradient Generator — before
CSS Gradient Generator — after
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AFTERBEFORE
14READY

CSS Gradient Generator

Create beautiful CSS gradients visually: pick colors, angle and type, then copy the ready-to-use code.

PX to REM Converter — before
PX to REM Converter — after
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AFTERBEFORE
15READY

PX to REM Converter

Convert pixels to rem and rem to pixels with any root font size, plus a quick reference table for common sizes.

Meta Tag Generator — before
Meta Tag Generator — after
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AFTERBEFORE
16READY

Meta Tag Generator

Generate SEO meta tags (title, description, Open Graph, Twitter) with a live Google search preview.

XML Formatter — before
XML Formatter — after
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AFTERBEFORE
17READY

XML Formatter

Format and validate XML online — beautify with 2 or 4 space indentation, minify, and catch syntax errors instantly.

YAML Formatter — before
YAML Formatter — after
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AFTERBEFORE
18READY

YAML Formatter

Format and validate YAML online with consistent indentation and instant error messages with line numbers.

SQL Formatter — before
SQL Formatter — after
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AFTERBEFORE
19READY

SQL Formatter

Format SQL queries online with proper indentation and keyword casing. Supports PostgreSQL, MySQL, SQLite, T-SQL and more.

JSON ⇄ YAML Converter — before
JSON ⇄ YAML Converter — after
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AFTERBEFORE
20READY

JSON ⇄ YAML Converter

Convert JSON to YAML and YAML to JSON online, both directions, with instant validation and clear error messages.