Base64 Converter – Encode & Decode Text Online

How to encode or decode Base64 text

1. Paste ordinary text into the input box and click Encode to Base64, or paste an encoded string and click Decode Base64.
2. For a URL or an application expecting Base64URL, select Encode as URL-safe Base64 before encoding.
3. Check the output box. Use Copy output or Download .txt, or move the result back to the input to reverse the conversion.

If the input is invalid Base64, or the decoded bytes are not valid UTF-8 text, the tool shows a specific error and leaves your input unchanged.

Base64 encoding examples

Text containing emoji and other non-English characters is first encoded as UTF-8 bytes. This prevents common errors caused by passing Unicode text straight into browser Base64 functions.

These last two values illustrate the alphabet change for the same bytes. In URL-safe Base64, + becomes - and / becomes _; padding is commonly omitted.

When to use standard Base64 vs Base64URL

Standard Base64 for text-safe data

Standard Base64 is a text representation of bytes. It appears in encoded message bodies, sample data and many developer workflows. Its alphabet includes + and /, with optional = padding at the end.

URL-safe Base64 for URL and token fields

Base64URL uses - and _ instead of + and /. Some protocols also omit padding. Choose it only when the receiving system expects that variant; Base64URL is not the same as ordinary URL percent-encoding.

UTF-8 text versus arbitrary binary data

This converter is for readable UTF-8 text. A Base64 string that represents a ZIP file, image or other binary data cannot reliably be shown as text; the tool reports invalid UTF-8 rather than displaying replacement characters. For image-format changes, use the dedicated Image Converter.

Common Base64 decoding errors

• Invalid characters: Text outside the standard or URL-safe alphabet cannot be decoded as Base64.
• Invalid padding: Extra or misplaced = characters are rejected. Missing padding is accepted when the remaining Base64 string is valid.
• Unreadable output: Correctly encoded binary bytes do not necessarily represent UTF-8 text.
• Wrong format: Base64 is not a way to validate an API token, decrypt a secret or convert a file to another image format.

Frequently asked questions

Is this Base64 converter free?

Yes. You can encode or decode text and copy or download the result without creating an account.

Can I decode Base64 containing line breaks?

Yes. Spaces and line breaks in encoded input are ignored. Other invalid characters still trigger an error.

Does Base64 encrypt or secure my text?

No. Anyone with the encoded string can decode it. Use appropriate security controls when handling credentials or private data.

Why won't a Base64 image decode into readable text?

Base64 can represent any bytes, including images. This page decodes only UTF-8 text, so binary content needs a file-aware decoder instead.

What is the difference between Base64 and URL encoding?

Base64 represents bytes using a limited text alphabet. URL encoding, also called percent-encoding, escapes characters for URL components. Use our URL Encoder/Decoder for that separate task.