splitforms.com
free · private · browser-side

Base64 decode and encode right in your browser.

Decode Base64 back to readable text, or encode text to Base64. UTF-8 safe, with a one-click direction toggle and instant copy. Nothing leaves your device.

Base64 input0 chars
Decoded text
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§ 02When to use it

Good fit

Inspecting JWT payloads, decoding data-url content, reading encoded tokens, debugging API responses, and quick encode/encode checks.

Bad fit

Decoding binary files like images or PDFs — use the Base64 to image tool for those, since raw text output would be garbled.

Form fields

Short tokens and IDs are fine as Base64. For files, send them as multipart/form-data through a real file input instead.

§ 04FAQ
What is Base64 decoding?

Base64 is a way to represent binary bytes using 64 printable characters. Decoding turns that string back into its original bytes, which for text means readable UTF-8.

Is this Base64 decoder UTF-8 safe?

Yes. It decodes the Base64 to bytes and then interprets them as UTF-8, so emoji, accented characters, and non-Latin scripts come out correctly — not as mojibake.

Can I encode text to Base64 here too?

Yes. Switch to the Encode tab, paste your text, and you get the Base64 output. Encoding uses UTF-8 bytes first, then Base64, so the result is portable.

Is my text uploaded anywhere?

No. Encoding and decoding run locally in your browser with atob and btoa. Nothing is sent to a server.

Why did decoding fail?

Base64 must be a multiple of 4 characters (padded with =) and use only A–Z, a–z, 0–9, +, and /. Stray quotes, spaces inside the string, or a truncated ending will cause an error. Trim the extras and try again.

Should I send Base64 in a form field?

Base64 is fine for short tokens and IDs. For files and large payloads, use multipart/form-data with a real file input — Base64 inflates size and is harder to validate server-side.

Ship forms that accept real files.

splitforms accepts file uploads on every plan — resumes, screenshots, PDFs, images. 500 submissions per month, free forever.

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