Base64 represents binary data using 64 printable characters (A–Z, a–z, 0–9, + and /), so it can travel safely through text-only channels like JSON, email and URLs. It is an encoding, not encryption — anyone can decode it.

A URL-safe variant that uses - and _ instead of + and / and drops the = padding. It is used in JWTs and URLs. Tick "URL-safe" to produce it; the decoder accepts both.

Is my data sent to a server?

No. Everything runs in your browser, so tokens, keys, passwords and other sensitive data you paste never leave your device.

Base64 Encoder & Decoder

Text to Base64.
And back again.

Text

Base64

To encode, choose Encode and type or paste text — the Base64 appears instantly; use "Encode a file" for images or other files (as a data URL). To decode, choose Decode and paste Base64; binary results can be downloaded as a file.

How to decode Base64

Choose Decode.
Paste the Base64 string (data: URLs and Base64URL are accepted).
Copy the decoded text, or download it if it is binary data.

Base64 in practice

Embedding small images in HTML or CSS as data URLs (data:image/png;base64,…).
Sending binary attachments in JSON APIs and email (MIME).
HTTP Basic authentication headers (Authorization: Basic …).
JWT tokens, which use the URL-safe Base64URL variant.

Why it matters that this runs locally

Many online developer tools send what you paste to a server — risky when it contains API keys, session tokens, customer data or proprietary code. This tool runs entirely in your browser: open your browser's Network tab and you will see that nothing you type is sent anywhere.

Frequently asked questions

What is Base64?: Base64 represents binary data using 64 printable characters (A–Z, a–z, 0–9, + and /), so it can travel safely through text-only channels like JSON, email and URLs. It is an encoding, not encryption — anyone can decode it.
What is Base64URL?: A URL-safe variant that uses - and _ instead of + and / and drops the = padding. It is used in JWTs and URLs. Tick "URL-safe" to produce it; the decoder accepts both.
Is my data sent to a server?: No. Everything runs in your browser, so tokens, keys, passwords and other sensitive data you paste never leave your device.