Overview
Paste a Base64 string or data URI to decode it into its actual bytes, then see each byte rendered as 3-digit, zero-padded octal (for example, byte 65 becomes "101"), space-separated. Like the Base64 to Binary and Base64 to Hex converters, this operates on the decoded `Uint8Array` directly, never on the character codes of a UTF-8-decoded string, so the result is correct even when the decoded bytes aren't valid text. Useful for teaching, low-level debugging, or working with systems that expect octal byte representations. Runs entirely client-side; nothing you paste is ever uploaded.
Best for: Seeing the exact bytes a Base64 string decodes to, in octal
How to use this tool
- Paste Base64 or a data URI. A data URI prefix is stripped automatically if present.
- Decoded to raw bytes. The Base64 string is decoded into a Uint8Array of actual bytes.
- Each byte becomes octal. Every byte is rendered as 3-digit, zero-padded octal, space-separated.
- Copy the result. Grab the full octal string with one click.
Why use this tool
Byte-aware, not character-aware
Decodes to real bytes first, so multi-byte UTF-8 or non-text binary content converts correctly.
Data URI support
Paste a full data URI and the base64 payload is extracted automatically.
Clear errors on invalid input
Malformed Base64 is flagged immediately instead of producing garbled output.
Nothing leaves your browser
Decoding happens entirely client-side.
Frequently asked questions
All three decode to the same raw bytes first; they differ only in the base used to display each byte - binary (base 2), octal (base 8), or hex (base 16).
A byte ranges from 0-255, and 255 in octal is "377" - three digits, zero-padded, is exactly enough to represent any byte value consistently.