AbsolTools
Base64 encoder
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Base64 encoder

Enter text or open a file. Convert UTF-8 text and binary files to standard Base64 or Base64URL without uploading them.

Encode text or files to Base64 online.

  • AbsolTools makes the tools you use often more accurate and convenient.
  • Every tool is free with no sign-up. Work happens in your browser, and inputs and results are not stored on or sent to a server.
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Drop a text or binary file anywhere in the converter.

Open this URL?

This URL was found in the decoded result. Check that it is safe and belongs to the site you expect.

Destination
Ready
Options
Interprets decoded bytes as text using this character encoding. It does not change the Base64 data itself.
Standard uses + and /. URL-safe uses - and _. Automatic accepts either alphabet.
Text uses the selected character encoding. Hex shows every decoded byte as a hexadecimal value.
Rejects non-canonical input instead of repairing whitespace, padding, or alphabet differences.
Treats each non-empty line as a separate Base64 value and keeps line breaks between the decoded results.
Removes whitespace, normalizes the URL-safe alphabet, and restores missing = padding when safe.
Keeps decoding when the readable result itself looks like Base64, up to the built-in safety limit.
Discards remaining non-Base64 characters after common repairs. Use only for damaged input.
Adds trailing = characters so the encoded length is a multiple of four.
Inserts a line break every 76 characters for MIME-style transfer formats.
Adds a data:...;base64, prefix for embedding the result in a URL, HTML, or CSS.

How to encode Base64

Base64 turns text or binary bytes into printable characters. It does not encrypt or protect the source data.

  1. Type text or open the file you want to encode.
  2. Choose standard Base64 or the URL-safe alphabet, then adjust padding or line wrapping only when the destination requires it.
  3. Copy the Base64 result or download it as a text file.

Your input is not stored.

The site does not store your input or conversion results, and it does not send them to a server. Everything is processed in your current browser session and disappears when you reload or close the page.

Standards and input handling

By default, the tool follows RFC 4648 and handles standard and URL-safe alphabets, optional padding, MIME whitespace, and Data URI prefixes. Turn on strict validation when the exact format matters.

Frequently asked questions

Is Base64 encryption?

No. Base64 changes binary data into printable text. It provides no secrecy or authentication.

Should I use standard Base64 or Base64URL?

Use standard Base64 for general files and data. Use Base64URL when the value must appear safely in a URL or filename.

Does this site upload my input?

No. Conversion happens in your browser. Your input, files, and results are not uploaded to a server.

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