Base64 Encode / Decode
Encode or decode Base64 — free, unlimited, and entirely private. Nothing leaves your browser.
How it works
Base64 represents binary data using only 64 printable ASCII characters, which makes it safe to embed inside text-only formats like JSON, XML, or URLs. This tool encodes and decodes Base64 directly inside your browser tab using built-in JavaScript APIs — no server, no upload, no waiting.
Text is converted to UTF-8 bytes before encoding, and decoded bytes are converted back from UTF-8, so round-tripping emoji and non-Latin scripts works correctly. If decoding fails, it usually means the input isn't valid Base64 — check for stray characters or missing padding.
Limitations
This tool works on text you paste directly; it doesn't yet accept file uploads for encoding a whole file to Base64. For very large inputs (tens of megabytes), your browser's memory is the only real limit — there is no artificial cap.
FAQ
- Is this Base64 tool really free?
- Yes — completely free, with no size limits and no account required. Everything runs in your browser, so there's no server cost to recoup.
- What is Base64 used for?
- Base64 turns arbitrary bytes into plain ASCII text, so binary data can be safely embedded in places that only accept text — JSON payloads, email attachments, data: URLs, or config files.
- Is my data uploaded anywhere?
- No — encoding and decoding both happen locally in your browser using built-in JavaScript APIs. Nothing you paste here is ever sent over the network, which makes it safe to use with production data.
- Does it handle emoji and non-Latin text correctly?
- Yes — input is encoded as UTF-8 bytes before Base64, so emoji, Cyrillic, Chinese, and other non-Latin text round-trip correctly, unlike naive Base64 tools that only handle Latin1 text.