Base64 Encoder — Encode Text to Base64 Online
Turn plain Unicode text into a standard Base64 string right in your browser. Paste the text, press encode, copy or download the result — nothing is ever uploaded, so the content you encode stays on your device.
Privately encoded in your browser — the text never leaves this tab.
Encoding runs entirely in this tab. Your text is converted with the browser’s built-in TextEncoder and never sent to any server — there is no request, beacon, analytics event or log that contains your input.
What it supports
- Input: any UTF-8 text — Latin, Cyrillic, Arabic, CJK, emoji.
- Output: standard Base64 (A–Z, a–z, 0–9, +, /) with padding.
- Copy to clipboard or download the output as a .txt file.
How it works
- 1
Paste your text
Type or paste any text — plain English, Cyrillic, Arabic, Chinese, or emoji.
- 2
Encode locally
Click Encode. The conversion runs in this browser tab using the built-in UTF-8 encoder.
- 3
Copy or download
Copy the Base64 value with one click or download it as a .txt file.
What this tool does
Base64 represents binary data as a safe ASCII string. This encoder takes the text you paste, converts it to UTF-8 bytes, and emits the standard Base64 form of those bytes. Because encoding happens on the UTF-8 bytes, characters such as Cyrillic, Arabic, Japanese and emoji produce valid, interchangeable output instead of the broken sequences you get from naive btoa() implementations.
Who it is for
Developers embedding text in JSON or email, QA engineers preparing test fixtures, writers sharing snippets that must not be mangled by transport layers, and anyone who needs a quick, private Base64 value without pasting sensitive content into a third-party web service.
Using the encoder
Paste or type text into the textarea, click Encode, and the Base64 value appears below. Use Copy to grab it, or Download to save it as a .txt file. Encoding is instant and happens locally, so there is no waiting and no file-size quota beyond what your browser can comfortably hold.
Standard Base64 explained
The output uses the standard alphabet with the + and / characters and optional = padding, which is what most JSON Web Tokens’ payload segment, data URLs and binary-string APIs expect. If you need the URL-safe variant (with - and _ instead), paste the value into the decoder section hint on the Base64 decode page — the two notations are not interchangeable.
Limits & notes
- Output is about 33% larger than the input (Base64 adds 4 characters per 3 bytes).
- Unicode is encoded as UTF-8 bytes first — this is correct behaviour, not a defect: the same bytes are what most APIs and filesystems expect.