Encode and decode Base64 strings
Built & maintained by Pappu Venkata Subbi Reddy, founder of Clacify
Base64 Encoder converts text to Base64 and back, instantly and entirely in your browser. Base64 is the encoding used to safely embed binary-adjacent data — images in CSS/HTML via data URIs, authentication tokens, email attachments — inside formats that only support plain text. Type or paste text, and it shows the Base64 result immediately; switch to decode mode to reverse it. Unlike a naive browser-native btoa()/atob() implementation, this tool correctly handles Unicode text (emoji, Hindi, Chinese characters, accented letters) by first encoding to UTF-8 bytes before Base64-encoding — a step many quick implementations skip, which causes them to throw an error or silently corrupt any non-ASCII character.
Base64 encoding takes binary data and represents it using only 64 printable ASCII characters (A–Z, a–z, 0–9, +, /), by regrouping the input's bits into 6-bit chunks and mapping each chunk to one of those 64 characters — which is why encoded output is roughly 33% larger than the original. The browser's native btoa() function only handles Latin-1 (single-byte) text correctly; feeding it a Unicode character like é or 🎉 either throws an error or produces garbage. This tool works around that by first passing the input through encodeURIComponent (which converts Unicode text into percent-encoded UTF-8 byte sequences) and unescape (which converts those sequences into raw bytes btoa can safely handle) before encoding — and reverses the exact same steps for decoding. The result is correct Base64 for any text you throw at it, not just plain English.
Base64 isn't encryption or compression — it doesn't hide data or make it smaller (it makes it about a third larger). Its only job is compatibility: taking data that might contain bytes a text-only format can't safely represent, and re-expressing it using only universally safe printable characters. This is why it shows up in so many unrelated places: a data: URI embeds a whole image file directly inside an HTML or CSS attribute as Base64 text (avoiding an extra network request for small icons); email's MIME format Base64-encodes attachments because raw binary data can corrupt in transit through mail servers designed for text; and HTTP Basic Authentication headers Base64-encode the username:password pair before sending, since header values must be printable ASCII.
Because Base64-encoded text looks unreadable at a glance, it's sometimes mistaken for a form of security or encryption — it is neither. Base64 is a public, reversible, one-to-one mapping with no key involved; anyone can decode it instantly with this exact tool, an online decoder, or a single line of code in any programming language. Encoding a password or API secret in Base64 provides zero protection against anyone who intercepts it — it only makes the data safe to transmit through text-only channels, not safe from being read. If you need to actually protect sensitive data, that calls for real encryption (with a secret key), not Base64.
Base64 encodes binary data as ASCII text, making it safe to transmit through systems that only handle text. Common uses: email attachments (MIME encoding), embedding images in CSS/HTML as data URLs, encoding credentials in HTTP Basic Authentication (base64(username:password)), and storing binary data in JSON.
Paste the Base64 string into Clacify's Base64 Encoder in Decode mode. The tool converts it back to the original text or binary representation. Base64 strings typically end with = or == padding characters.