Base64 Encoder
Encode text as Base64 — the standard way to safely embed binary data in text-only contexts. Unicode-aware.
0 characters
0 characters
About Base64 Encoder
Base64 encodes bytes into a sequence of 64 printable ASCII characters (A–Z, a–z, 0–9, +, /, with = for padding). It's the standard way to embed binary data — images, certificates, raw bytes — in JSON, URLs, email headers, and other text-only contexts. This tool encodes your input as UTF-8 bytes first, then Base64, so non-ASCII text round-trips correctly.
When to use it
- Embedding an image or font as a data URI in CSS
- Encoding binary content for inclusion in JSON or YAML
- Producing a Base64 payload for an HTTP Authorization header
- Sending Unicode strings through systems that mishandle multi-byte characters
How it works
The input string is encoded as UTF-8 via TextEncoder, then the byte sequence is converted to Base64 via btoa. The output uses the standard alphabet with '=' padding.
Examples
Hello, world!
SGVsbG8sIHdvcmxkIQ==
Unicode characters encode as their UTF-8 bytes
café 🎉
Y2Fmw6kg8J+OiQ==
Frequently asked questions
- Is the output URL-safe?
- No — standard Base64 uses + and /, which are reserved in URLs. For URL-safe Base64 (- and _), post-process with find-and-replace.
- Does it handle Unicode?
- Yes. The input is encoded as UTF-8 before Base64 encoding, so emoji and non-Latin scripts survive the round-trip via base64-decode.
- Is Base64 encryption?
- No. Base64 is reversible by anyone. Use it to make data transport-safe, never to keep it secret.