Base64 Encoder / Decoder

How Base64 Encoding Works

Base64 is a binary-to-text encoding scheme that represents arbitrary bytes using 64 printable ASCII characters: A-Z, a-z, 0-9, plus '+' and '/', with '=' for padding. When you paste text or drop a file into Toolkiya, the browser reads the raw bytes, groups them into 24-bit chunks, then splits each chunk into four 6-bit indices that map to the Base64 alphabet.

Decoding reverses the process: each character is converted back to its 6-bit index, the bits are concatenated, and the resulting bytes are returned either as a UTF-8 string or as a downloadable file. Everything runs through the native btoa, atob, and TextEncoder APIs inside your tab — no network round trip, no temporary upload, no server log.

When to Use Base64

Embedding small images or fonts directly into CSS or HTML as data URIs. Encoding binary payloads inside JSON, JWTs, or environment variables. Inspecting the contents of a Base64 string pasted from a config file, email header, or API response. Encoding credentials for HTTP Basic Auth during local testing. Decoding email attachments saved from .eml files to recover the original binary.

Why Encode Base64 in Toolkiya

Base64 is often used for sensitive material — API tokens, private keys, signed payloads. Pasting that into a random online encoder means the operator can read it. Toolkiya never sends your input anywhere; encoding and decoding happen entirely in your browser's JavaScript runtime.

There is no upload size cap beyond what your device's memory allows, no signup, no rate limit, no daily quota, and no ads injected into the output. You can encode a multi-megabyte file just as easily as a single line of text, and close the tab knowing nothing was retained.

Tips for Base64 Encoding

Use URL-safe Base64 (replace '+' with '-' and '/' with '_') when embedding tokens in query strings or JWTs. Remember Base64 inflates size by roughly 33% — it is not compression. Strip whitespace and line breaks before decoding strings copied from emails, since some encoders wrap output at 76 characters. For binary files, prefer the file mode rather than pasting raw bytes into the text box.