55 tools · 100% client-side · no sign-up
The developer toolbox that never leaves your browser
Format JSON, minify code, decode a JWT, generate a hash or convert a colour — 55 free tools that run entirely on your machine. Nothing you paste is uploaded or logged.
Popular tools
The ones people reach for most often.
- Encoders & Decoders
Base64 Decode
Decode Base64 back to text — accepts both alphabets and any line wrapping automatically.
- Encoders & Decoders
Base64 Encode
Encode any text to Base64 — full UTF-8 support, with optional URL-safe output.
- Text Tools
Case Converter
Convert between twelve naming conventions — camelCase, snake_case, kebab-case, Title Case and more.
- Text Tools
Character Counter
Count characters against the limits that matter — SEO titles, meta descriptions, X, SMS — with correct emoji handling.
- Color Tools
Color Contrast Checker
Check any text colour against any background for WCAG AA and AAA — a whole palette at a time, with alpha composited properly.
- Color Tools
Color Converter
Convert a colour between every common format — including OKLCH — with WCAG contrast ratios included.
- Color Tools
Color Picker
Pick a colour visually and get every format, a tint/shade ramp and live WCAG contrast feedback.
- Code Formatters
CSS Formatter
Expand and tidy stylesheets with consistent indentation and spacing.
- Converters
CSV to JSON
Convert CSV, TSV or any delimited text to JSON with correct handling of quotes, commas and embedded newlines.
Browse by category
11 categories, from JSON and formatters to cryptography and colour.
Why client-side matters
Nothing is uploaded
Every tool runs in your browser. Your JSON, tokens and passwords never touch a server — ours or anyone else’s.
Instant results
No round-trip, no queue, no rate limit. Output updates as you type, and heavy libraries load only for the tool that needs them.
Works offline
Because the logic is client-side, a tool keeps working once its page has loaded — useful on a plane or a bad connection.
No sign-up, ever
No account, no email wall, no free-tier limits. Open the page and use it.
From the blog
Guides and deep dives on the things these tools touch.
Developer Tools8 min readThe Caret Range Changes Meaning Below Version 1.0
A caret range allows every future minor, unless the version starts with zero. It then narrows, and those dependencies quietly freeze.
The TweakPad Team
Web Development8 min readYour noindex Stops Working the Moment You Block the Page
Adding noindex and a robots.txt block together is worse than either alone. Google never reads the rule on a page it cannot crawl.
The TweakPad Team
Backend & Databases8 min readPostgres Logical Replication Does Not Send You the Old Row
Logical replication sends the new row and, by default, no before-image at all. What Postgres puts in an UPDATE, and what it leaves out.
The TweakPad Team
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