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Random Bytes Generator

Generate cryptographically secure random bytes in hex, base64, or base64url in your browser using the WebCrypto API.

Learn more: JWT & Web Tokens ExplainedHow JSON Web Tokens work — structure, signing (HS256 vs RS256), claims, verification and best practices.

Runs entirely in your browser — nothing you enter is uploaded or stored.

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Random Bytes Generator

Generate cryptographically secure random bytes in hex, base64, or base64url in your browser using the WebCrypto API.

Paste your input on the left and the result is produced instantly — entirely in your browser. Your data never leaves the page, which you can confirm from the Network panel or our privacy policy.

Frequently asked questions

How do I use the Random Bytes Generator?

Paste or type your input on the left, set the options, and the random bytes appears on the right — copy or download it. Everything runs in your browser.

Is my data uploaded anywhere?

No. This tool runs entirely in your browser — your input is never sent to a server. You can verify it in the Network tab or in our Content-Security-Policy.

Is the Random Bytes Generator free?

Yes — completely free, no sign-up and no limits. Everything happens client-side.

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