Related tools
Base64 Encoder
Base64 encodes binary data (or Unicode text) into ASCII using A–Z, a–z, 0–9, +, and /. That lets you embed or transmit bytes through text-only systems such as JSON, XML, or email. This page runs entirely in your browser—your content never uploads to our servers. You can type text or load a file and copy the resulting string.
When to use Base64 Encoder vs other options
Use this tool when you already have text or a file and need the Base64 representation—for example data URIs in HTML or CSS, API fields that expect encoded bytes, or sharing binary through chat or logs. Use our decoder page when you start from a Base64 string and need the original content back. Base64 is not encryption; pair it with real cryptography if you need secrecy. For checksums or fingerprints, use a hash generator instead.
Compatibility
Standard RFC-style Base64 is widely supported across languages and platforms. Some environments expect URL-safe variants (often substituting +/ with -_). This encoder outputs standard Base64; convert characters if your target requires URL-safe form. Because everything stays client-side, you can safely experiment without shipping data over the network.
Quality considerations
Encoding is lossless: decoding with a compatible tool restores the exact bytes you started from (when padding is correct). Expect roughly a 33% size increase compared with raw binary. Avoid treating Base64 as protection for passwords or secrets—anyone can decode it—and be mindful of huge files, which produce very long strings that may slow down the browser.
Example use cases
- Build data URIs for small images or fonts when prototyping HTML or CSS.
- Prepare payloads for APIs or configuration files that store Base64 blobs.
- Move binary through systems that only allow plain text in transit.
- Generate strings for tooling or tests that expect Base64 input.
- Turn a local file into a pasteable string when binary upload is not available.
Base64 encoding runs fully in your browser with no server upload; output updates instantly and stays private on your device.