Base64 Encoder / Decoder

Encode text to Base64 or decode Base64 back to text. 100% free, no signup. Everything runs in your browser.

100% free No sign-up Private by design Works on any device
Base64 Encoder / DecoderRuns locally

This free Base64 encoder and decoder converts text to Base64 and back instantly, with full UTF-8 support. That means accented characters, non-Latin scripts and emoji survive the round trip intact. Base64 is everywhere in modern computing. It is how email attachments travel, how images get embedded in CSS as data URIs, how HTTP Basic Auth credentials are transmitted, and how JSON Web Tokens package their payloads. When you need to encode a string for an API, or decode a Base64 blob you found in a config file or a token, this tool does it in your browser with nothing uploaded or logged. Choose Encode or Decode, paste your text, and the result appears as you type.

How to use

  1. Choose the mode: Encode to turn plain text into Base64, or Decode to turn Base64 back into readable text.
  2. Paste or type your input. The result appears instantly, no button needed.
  3. Encoding example: 'Hello' becomes 'SGVsbG8='. The trailing equals signs are padding and belong to the output.
  4. When decoding, paste the Base64 string exactly, including any equals padding at the end.
  5. If decoding fails, check for missing characters, line breaks added by an email client, or URL-safe variants that swap plus and slash for dash and underscore.
  6. Click Copy to grab the output for your code, API request or config file.

Why use our base64 encoder / decoder?

The main reason to use this converter is that it runs entirely on your device. Base64 strings often contain things you should never paste into random websites: API credentials, auth headers, token payloads, configuration secrets. Here, encoding and decoding happen in your browser and nothing leaves your machine. Full UTF-8 handling is the second win. Many quick converters mangle emoji and non-English characters because they ignore character encoding. This one gets 'héllo 👋' right in both directions.

It is also honest about what Base64 is: an encoding, not encryption. Anyone can decode it, so never use it to protect secrets. For real credentials, create something strong with the password generator. In daily developer work it slots in next to the JSON formatter: decode a JWT segment here, then pretty-print the JSON payload there. And when you want to move an encoded snippet from screen to phone, the QR code generator does it in seconds.

Who is this tool for?

Developers use Base64 constantly: building Basic Auth headers, embedding small images as data URIs in CSS, inspecting JWT payloads while debugging authentication, and encoding content for JSON APIs that only accept text. DevOps engineers meet it in Kubernetes secrets, which are Base64 encoded by design, and in CI environment variables and certificate bundles.

QA engineers decode tokens and webhook payloads while reproducing bugs. Security analysts and IT support decode Base64 strings found in email headers, logs and suspicious scripts to see what they actually contain. Students learning web development use it to understand how data URIs and HTTP authentication really work. Email admins troubleshoot MIME encoded message parts. Even no-code builders occasionally hit an API that demands Base64 input. Paste, encode, done.

Frequently asked questions

Is Base64 encryption?

No, and this matters. Base64 is a reversible encoding that anyone can decode. It provides zero secrecy, so never use it to protect passwords or sensitive data. Use real encryption for security.

Does this support Unicode and emoji?

Yes, full UTF-8 support in both directions. Accented characters, non-Latin scripts and emoji encode and decode correctly. Many simpler tools get this wrong.

Is my data sent to a server?

No. Encoding and decoding happen entirely in your browser, which makes it safe for tokens, credentials and internal data.

What are the equals signs at the end of Base64?

Padding. Base64 works in blocks of 3 input bytes, and the equals signs fill the final block when the input length is not a multiple of 3. They are part of the string, so keep them when copying.

Why does Base64 make my data bigger?

Base64 represents every 3 bytes as 4 text characters, so the output is about a third larger than the input. That is the price of making arbitrary data safe for text-only channels.

Why won't my Base64 string decode?

The usual causes: characters missing from the start or end, line breaks added by an email client, or a URL-safe variant that replaces plus and slash with dash and underscore. Fix those and try again.

What is Base64 actually used for?

Email attachments, data URIs for inline images, HTTP Basic Auth, JWT tokens, Kubernetes secrets, and any place binary data has to travel through text-only channels.

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