Base64 Encoder & Decoder
Encode and decode Base64 — UTF-8 safe, with a URL-safe option.
Base64 turns any text into a compact string of safe ASCII characters so it can travel through systems that only accept plain text — data URIs, JSON fields, email attachments, and the segments of a JWT. Type your text and press Encode, or paste a Base64 string and press Decode. Encoding is UTF-8 safe, so accents and emoji survive the round trip, and the URL-safe option produces output you can drop into a URL or filename without escaping. Everything runs in your browser — nothing you type is uploaded — and it keeps working offline once loaded. Remember that Base64 is an encoding, not encryption: it is fully reversible by anyone, so never use it to hide secrets.
Frequently Asked Questions
What is Base64?
Base64 is a way of representing binary or text data using only 64 printable ASCII characters (A–Z, a–z, 0–9, + and /). It is used wherever arbitrary data must travel through a text-only channel — embedding images in CSS or HTML as data URIs, encoding email attachments (MIME), storing binary blobs in JSON or XML, and packing the segments of a JSON Web Token. Encoding groups the input into 6-bit chunks and maps each to one character, which makes the output about a third larger than the original. It is completely reversible: decoding maps the characters back to the original bytes. This tool encodes the text you type into Base64 and decodes Base64 back to text, all in your browser.
Is Base64 encryption or secure?
No. Base64 is an encoding, not encryption, and provides no security whatsoever. Anyone can decode a Base64 string instantly — including this tool — because the transformation uses a fixed, public alphabet with no key involved. Treat Base64 purely as a transport format for moving data through text-only systems, never as a way to hide passwords, tokens, or sensitive information. If you need to keep data secret, use real encryption (such as AES) or a hashing function for verification; Base64 only changes how bytes are written down, not who can read them. A common mistake is assuming a Base64-looking string is protected — it is not.
Does it handle accents and emoji (UTF-8)?
Yes. Plain browser Base64 functions only handle single-byte characters and break on accented letters or emoji, so this tool first encodes your text as UTF-8 before converting to Base64, and reverses that step when decoding. That means characters like é, ñ, 漢字, and 🚀 round-trip correctly: encode them and decode the result, and you get exactly what you started with. The same UTF-8 handling applies in both directions, so pasting a Base64 string that contains multi-byte characters decodes to the right text rather than mojibake. If you ever see garbled output, double-check that the input really is valid Base64 and was produced with UTF-8 encoding.
What is the URL-safe Base64 option?
Standard Base64 uses + and / characters and = for padding, all of which have special meaning in URLs and filenames. The URL-safe variant (RFC 4648 §5) replaces + with - and / with _, and usually drops the trailing = padding, so the result can be dropped straight into a query string, path, or filename without escaping. JSON Web Tokens use exactly this variant for their header and payload segments. Tick the URL-safe box in this tool to produce that form when encoding; when decoding, it accepts both the standard and URL-safe alphabets automatically and restores any missing padding for you, so you do not have to think about which variant you were given.
Is my data private?
Yes. Everything happens locally in your browser using built-in JavaScript — the text you type and the Base64 you paste are never sent to a server, logged, or stored. There is no account, no sign-up, and no tracking of the values you convert, so it is safe to use for config snippets or data you would rather not upload to a random website. Because the work is local, the tool also keeps working offline once the page has loaded. That said, remember Base64 is not secret: even though we never see your data, anyone you hand the encoded string to can decode it just as easily.