Base64 Encoder & Decoder

Client-sideNo sign-upFree

Convert text to and from Base64 encoding instantly.

How this tool works

1

Choose a direction

Pick Encode to convert plain text to Base64, or Decode to reverse it.

2

Paste your text

Drop in the string you want converted - an API token, a config value, anything.

3

Read the result instantly

The output updates live as you type, with no button press required.

4

Swap and repeat

Use the swap button to feed the output straight back in as new input.

Quick facts

Category
Encoders & Decoders
Best for
Embedding binary data in URLs or JSON payloads
Plain text
Base64
Rm9ybWF0aXEgbWFrZXMgZGV2IHRvb2xzIGZhc3Qu
✓ Done
In-content slot

About this tool

Encode plain text into Base64 or decode Base64 back into readable text, with a mode toggle to switch between the two directions and a swap button to feed the output straight back in as input. Base64 exists because some systems (older email protocols, certain URL contexts, JSON fields) can only reliably carry plain ASCII text, so binary or special-character data gets re-encoded into a safe 64-character alphabet before being embedded, then decoded back on the other end. Commonly used for embedding data in URLs, email attachments, and API payloads that require ASCII-safe encoding, or for quickly reading what a Base64-encoded JWT segment or config value actually contains. Runs fully client-side, so nothing you paste is ever uploaded.

Why use this tool

Runs entirely offline-safe

Encoding and decoding happen in your browser - nothing you paste is ever transmitted anywhere.

One tool, both directions

No need to hunt for separate encode and decode tools - switch instantly with a single toggle.

Live as you type

See the converted output update in real time, with no button to click or page to wait on.

Handles real payloads

Works cleanly with long strings like JWT segments, API tokens, and embedded binary data.

Frequently asked questions

Base64 converts binary or text data into an ASCII string, commonly used to embed images in HTML/CSS, attach files to emails, or pass data safely through URLs and JSON.

Base64 decoding fails when the input contains characters outside the standard Base64 alphabet or has incorrect padding — double check you copied the full encoded string.

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