Base64 converter

Text to bytes to Base64

Encoding converts text to UTF-8 bytes before Base64, so ordinary accented text and emoji are supported. Standard output uses + and / with padding; URL-safe output uses - and _ and omits padding.

Decoding accepts padded or unpadded input in the chosen alphabet and ignores ASCII spaces, tabs and line breaks. Invalid padding bits and invalid UTF-8 bytes are rejected. A leading UTF-8 byte-order mark is preserved as a text character. This is a text tool, not a binary-file viewer.

Encoding does not protect secrets

Base64 changes a representation; it is not encryption and does not hide information from someone who can decode it. The converter operates locally, without uploading your text.

Local text processing

The input is processed in this browser and is not sent to our servers or included in tool-use analytics. Use up to 20,000 UTF-16 input units at a time. Copy output keeps your original input intact; if clipboard access is blocked, the output is selected for manual copying.

Questions

• Why does a valid Base64 string fail to decode here? Base64 can represent arbitrary binary bytes. This tool only returns valid UTF-8 text, so a binary image, compressed file or non-UTF-8 encoding can be rejected.
• What is URL-safe Base64? It uses - and _ in place of + and /. This tool omits padding when encoding URL-safe output and accepts optional valid padding when decoding.