Base64 converter
Encode text to Base64, or decode Base64 to text.
In short
Encode text to Base64 or decode a Base64 string back to plain text.
What Is Base64?
Base64 is an encoding scheme that converts binary data into a set of 64 printable ASCII characters. It is used to safely transmit binary content over text-based systems — such as embedding images in CSS or encoding credentials in HTTP headers.
Common Uses for Base64
Base64 encoding is used in Basic HTTP authentication headers, data URIs for inlining images and fonts in CSS, email attachments (MIME encoding), and JSON Web Tokens (JWTs).
If you have ever seen a long string of letters and slashes ending in == in a URL or header, it is likely Base64-encoded data.
Best For
- Developers encoding credentials for HTTP Basic Auth headers
- Frontend engineers inspecting or building data URIs
- Backend developers debugging JWT payloads
- Anyone decoding Base64 strings from logs or API responses
Limitations of this tool
- Base64 is not encryption — do not use it to protect sensitive data.
- Very large inputs may be truncated before processing.
Frequently asked questions
- Is Base64 a form of encryption?
- No. Base64 is an encoding scheme, not encryption. It is reversible without a key — anyone can decode a Base64 string. Do not use it to protect sensitive data.
- Why does Base64 end in == ?
- Base64 encodes data in groups of 3 bytes. When the input is not a multiple of 3, padding characters (=) are added at the end to complete the group.
- What is a JWT?
- A JSON Web Token is a compact token format that encodes claims as Base64-encoded JSON. The header and payload sections of a JWT are Base64url-encoded and can be decoded with this tool.
- What is a data URI?
- A data URI embeds a file's content directly in a URL using Base64 encoding (e.g. data:image/png;base64,...). It is used to inline images or fonts without a separate network request.
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Category: Utilities · Last updated 2026-11-03T04:04:56+00:00