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Base64 decoder and encoder online

To encode or decode Base64 online, paste your text and click Encode or Decode. The tool converts text to Base64 (or Base64 back to text) instantly in your browser with no data upload.

Convert text to Base64 and back for data URLs, basic auth headers, and quick debugging. One tool for both directions—no install required.

Last updated: 2026-04-12

✓ All processing happens in your browser ✓ No sign-up required ✓ 70 developer tools available ✓ Built by developers, for developers

What is Base64 Encode & Decode?

Base64 Encoder & Decoder converts text to Base64 and Base64 back to text, all in your browser. Use it for data URLs, basic auth headers, and quick debugging.

Benefits of Base64 Encode & Decode

  • Quick encoding without writing code
  • Safe handling of sensitive tokens
  • Works with data URLs for embedded images
  • No dependency on command-line tools

Features

  • Bidirectional encoding and decoding
  • Handles Unicode text correctly
  • Instant results with no server upload
  • Copy output with one click
  • Shows output size comparison

Common use cases

  • Decoding Base64 segments from JWTs
  • Creating data URLs for small images
  • Encoding credentials for Basic Auth headers
  • Debugging Base64-encoded API payloads

Quick steps to use Base64 Encode & Decode

  1. Scroll to the workspace below—this same page loads the interactive tool.
  2. Paste or type your input, then run the primary action.
  3. Copy the output or switch tabs to another Developer Friend utility.
  4. For long documents, combine with our JSON formatter, diff, or API tester as needed.

Detailed guide and reference: Base64 Encode & Decode

How to Use Base64 Encode & Decode

  1. Enter your text — Type or paste the text you want to encode or decode in the input field.
  2. Choose direction — Select Encode to convert text to Base64, or Decode to convert Base64 back to text.
  3. Copy the output — Click the copy button to grab the result for use in data URLs, headers, or configuration files.

What is Base64 used for?

Base64 represents binary data as ASCII text. You will see it in data URLs for small images, in email and MIME attachments, and when APIs return binary payloads as text. It is not encryption—anyone can decode it—so never rely on Base64 alone to protect secrets.

Encode and decode in JavaScript

Browsers expose btoa and atob for binary strings where each character is in the Latin-1 range. For Unicode strings, you need a UTF-8 conversion step first, which trips many people up.

// Latin-1 safe btoa("hello"); // aGVsbG8= // Unicode: convert to UTF-8 bytes first (e.g. TextEncoder) // or use our tool to avoid boilerplate

Decoder vs encoder: same tool

Whether you need a Base64 decoder for a JWT segment or an encoder for a config blob, use the same page: paste the input and choose the direction. For images, see also our image to Base64 helper.

Privacy-friendly Base64 online

Credentials and tokens should not be pasted into untrusted websites. Developer Friend runs the conversion locally in your tab so sensitive strings are not uploaded as part of the tool workflow.

Example Usage

Encode text to Base64

Input:

Hello, World!

Output:

SGVsbG8sIFdvcmxkIQ==

Convert plain text into Base64-encoded form for data URLs or API headers.

Decode Base64 to text

Input:

ZGV2ZWxvcGVyIGZyaWVuZA==

Output:

developer friend

Reverse Base64 encoding to reveal the original text content.

Key Features and Benefits

Key Features

  • Bidirectional encoding and decoding
  • Handles Unicode text correctly
  • Instant results with no server upload
  • Copy output with one click
  • Shows output size comparison

Benefits

  • Quick encoding without writing code
  • Safe handling of sensitive tokens
  • Works with data URLs for embedded images
  • No dependency on command-line tools

Common Use Cases

  • Decoding Base64 segments from JWTs
  • Creating data URLs for small images
  • Encoding credentials for Basic Auth headers
  • Debugging Base64-encoded API payloads

Best Practices

Common Mistakes to Avoid

How this compares to alternatives

Command-line Base64 (openssl base64, base64) is ideal for scripts and pipes. Browser tools suit quick decode of JWT segments, data URLs, or snippets from logs. Developer Friend avoids sending your paste to a third-party server.

Frequently Asked Questions about Base64 Encode & Decode

What is Base64 encoding?

Base64 converts binary data into ASCII text using 64 characters (A-Z, a-z, 0-9, +, /). It is used for data URLs, email attachments, and embedding binary in text formats.

Is Base64 encryption?

No. Base64 is encoding, not encryption. Anyone can decode it. Do not use Base64 alone to protect sensitive data.

How do I decode Base64 in JavaScript?

Use atob() for simple ASCII strings, or TextDecoder with Uint8Array for Unicode-safe decoding.

Is the Base64 Encode & Decode on Developer Friend free?

Yes. Base64 Encode & Decode and every other utility on Developer Friend are free to use in your browser. There is no sign-up wall and no paywall for core features.

Does my data leave my device when I use Base64 Encode & Decode?

By default, Base64 Encode & Decode runs entirely in your browser. Your input is not uploaded to Developer Friend servers unless the tool explicitly performs a network request you start (for example, an API test or DNS lookup).

Can I use Base64 Encode & Decode offline?

After the first load, Developer Friend is cached by your browser and most tools work offline. Tools that need live network access still require a connection.

Who is Developer Friend for?

Developer Friend is built for software engineers, QA, DevOps, and technical writers who need fast formatters, encoders, and API helpers without installing desktop software.

How many tools are on Developer Friend?

Developer Friend offers 70+ free developer tools across JSON, API, encoding, time, Dev, and AI-assisted workflows.

Often opened next by developers

Static suggestions based on common workflows (your own recently used tools appear in the app when JavaScript runs).

About Developer Friend

Developer Friend is a free workspace with 70+ developer tools for JSON, APIs, encoding, time math, Dev utilities, and optional AI-assisted explainers. It is built for engineers who want fast answers in a browser tab without installing desktop software.

Privacy assurance

All processing happens in your browser for tools that do not initiate a network call. Sensitive payloads like JWTs, .env excerpts, and SQL drafts stay on your device unless you deliberately use a networked feature.

Why teams trust the platform

The interface is keyboard-friendly, theme-aware, and consistent across tools so you can move from formatting JSON to testing an API without relearning controls. There are no paywalls on core utilities and no sign-up requirement for day-to-day use.