utilitybelt.dev

Base64 Encoder/Decoder

Encode plain text to Base64 or decode Base64 back to readable UTF-8 text instantly in your browser.

Base64 workbench

Encode plain text into Base64 or decode Base64 back to readable UTF-8 text. Everything runs locally in your browser.

Choose a mode, paste text, then convert.

Unicode-safe

Handles emojis and international text using UTF-8 before Base64 conversion.

Private by default

Input is processed client-side and is not uploaded to UtilityBelt.dev servers.

Clear validation

Invalid characters, bad padding, and non-text binary payloads produce readable errors.

What is Base64 Encoder/Decoder?

The Base64 Encoder/Decoder is a fast browser-based utility for turning plain text into Base64 or decoding Base64 strings back into readable UTF-8 text. It is useful when you are debugging API payloads, preparing text for transport through systems that expect ASCII, inspecting encoded configuration values, or checking the readable portion of a token-like string. The workbench stays at the top of the page so you can paste, convert, copy, and swap modes without sending content to a server.

Common Use Cases

  • Encoding text snippets, JSON, or configuration values for systems that require Base64 text.
  • Decoding Base64 found in logs, headers, data URLs, scripts, or API responses.
  • Checking whether an encoded value is valid Base64 before adding it to code or documentation.
  • Quickly converting Unicode text, including emojis and international characters, through UTF-8-safe Base64.

Base64 examples

ScheduleCron expressionPlain-English conversion
Plain textHello worldEncodes to SGVsbG8gd29ybGQ=
JSON snippet{"env":"prod"}Encodes text safely for config examples or docs.
UnicodeDeploy ✅UTF-8 handling preserves non-ASCII characters during round trips.

Example: Input & Output

Sample Input

See the tool above for interactive examples.

Expected Output

The processed output will appear here instantly.

How to Use

  1. Step 1: Choose Encode to convert plain text into Base64, or Decode to convert Base64 back to text.
  2. Step 2: Paste your input into the workbench. Whitespace in Base64 input is ignored during decoding.
  3. Step 3: Click the convert button or use the keyboard shortcut to generate the result.
  4. Step 4: Copy the result or swap it back into the input to reverse the operation.

Frequently Asked Questions

Is Base64 encryption?

No. Base64 is an encoding format, not encryption. Anyone can decode a Base64 string, so do not treat it as a way to hide secrets.

Does this Base64 tool upload my input?

No. Encoding and decoding happen locally in your browser. UtilityBelt.dev does not receive or store the text you paste into the tool.

Why does decoding fail for some Base64 strings?

The input may contain invalid characters, malformed padding, or binary bytes that are not valid UTF-8 text. This tool focuses on Base64 strings that decode to readable text.

Can I decode JWTs with this tool?

JWTs use Base64URL segments and contain structured header and payload data. Use the JWT Decoder when you need token-specific parsing.

Privacy & Security

All data processing for the Base64 Encoder/Decoder happens entirely on your local machine within your browser. No data is ever sent to our servers, ensuring your information remains private and secure. We believe in privacy by design, and our tools are built to be used without compromising your data.