The little tools you reach for, in one quiet place

Free online developer tools

Format some JSON, decode a token, hash a string, mint a UUID. Every tool on Plybyte runs entirely in your browser, with no account to create, nothing uploaded, and no tab full of ads getting in the way.

Open a tool Read the guides

Free forever · works offline once loaded · nothing leaves your machine

Pick a tool, get to work

Nine focused utilities, each doing one job well. No wizards, no dashboards. Open it and paste.

JSON Formatter Pretty-print, validate and minify JSON with clear error messages. Base64 Encode text to Base64 or decode it back, instantly and offline. URL Encoder Percent-encode or decode URLs and query components safely. Hash Generator Compute MD5, SHA-1, SHA-256, SHA-384 and SHA-512 digests of any text. UUID Generator Mint random version-4 UUIDs one at a time or in bulk. JWT Decoder Inspect the header and claims of a JSON Web Token at a glance. Regex Tester Test a JavaScript regular expression and see every match highlighted. Timestamp Converter Convert between Unix epoch time and human-readable dates. JSON to CSV Convert a JSON array of objects to CSV, and CSV back to JSON.

It stays on your machine

Every tool does its work in client-side JavaScript. Your JSON, tokens and text are never sent to us, because there is no server to send them to.

No account, nothing to install

Nothing to sign up for and nothing to download. Open a tool and it works right away, and it keeps working offline once the page has loaded.

Open and inspectable

No analytics and no tracking. The only third-party code is Google AdSense, and it loads only after you accept advertising cookies. Until then, your browser's network tab shows requests to exactly one origin: this one.

From the guides

All guides

Reading a JWT without fooling yourself

Decoding a JSON Web Token shows its claims, but not whether to trust them. Understand the difference between decoding and verifying a JWT, and why it matters.

2 min read

Base64 and Unicode, the part that bites you

Naive Base64 encoding mangles anything beyond ASCII. Learn why it breaks and the one UTF-8 step that makes emoji and accents survive the round trip every time.

1 min read

Questions, answered plainly

Is my data really never uploaded?

Correct. The tools are plain JavaScript that runs in your browser, so the text you paste is processed on your own device and never sent anywhere. Aside from Google ads if you choose to accept them, the page and its assets load from this single origin.

Do I need an account?

No. Every tool works with zero setup, so open the page and start. There is no account to create and nothing to install.

Can I use Plybyte offline?

Once a tool's page has loaded, it keeps working without a connection, because the logic already lives in your browser. Refreshing while offline will of course need the page to be cached first.

Is it free, and how is it funded?

Every tool is free. The site is supported by ads, which load only if you accept cookies and never see what you paste, because that is processed entirely in your browser.

Bookmark it and forget about it.

Next time you need to untangle some JSON or peek inside a token, it will be right where you left it.

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