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The dev tools you
actually reach for.

10 browser utilities for developers.
No tracking. No servers. Your data never leaves your device.

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Formatters

data_object
JSON Formatter & Validator
Format, minify, and validate JSON with inline error messages.
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article
Markdown Previewer
Write Markdown, see live HTML output side by side.
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Encoding / Decoding

lock_open
Base64 Encoder & Decoder
Encode or decode Base64 strings. Fully private, no server.
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link
URL Encoder & Decoder
Percent-encode or decode URLs and query strings.
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verified_user
JWT Decoder
Inspect JWT header, payload, and expiry at a glance.
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Generators

fingerprint
UUID Generator
Generate 1–100 UUID v4 strings using the Web Crypto API.
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Converters

schedule
Unix Timestamp Converter
Live epoch counter, timestamp→date, and date→timestamp.
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palette
Color Converter
Convert between HEX, RGB, and HSL. Visual picker included.
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Testers

manage_search
Regex Tester
Live match highlighting, flags, and capture group table.
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timer
Cron Expression Builder
Build cron expressions visually with plain-English descriptions.
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