100% free · no upload · private

Base64 Encode & Decode Online

Encode text or files to Base64 and decode Base64 strings back to their original form. Instant results, no server calls — a fast utility for developers and power users.

Open Base64 Tool

No software required · Works in any browser

Text & File Support

Encode plain text, JSON payloads, images, PDFs, or any binary file. Decode Base64 back to the original content instantly.

Instant Results

Output appears as you type. No submit button needed for text mode — the encoded or decoded value updates in real time.

Nothing Leaves Your Device

Encoding and decoding happen with JavaScript in your browser. No data is sent to any server, ever.

Copy or Download

Copy the result to your clipboard with one click, or download decoded binary data as a file ready to use.

How It Works

1

Choose Mode

Select Encode or Decode. Then pick whether you are working with text input or a binary file.

2

Paste or Drop

Type or paste your text, or drag and drop a file. For decoding, paste the Base64 string you want to convert back.

3

Copy the Result

The output appears immediately. Click copy to grab it, or download the decoded file directly to your device.

Common Use Cases

Embedding Images in HTML/CSS

Encode small icons and SVGs to data URIs for inline embedding, avoiding extra HTTP requests in your web pages.

API Debugging

Decode Base64 payloads from JWTs, webhooks, or API responses to inspect their contents without writing code.

Email Attachment Inspection

Raw email files encode attachments in Base64. Decode them to extract the original document or image.

Configuration & Secrets

Many CI/CD systems store secrets as Base64 strings. Quickly encode values or decode them to verify contents.

Superconverter vs Others

FeatureSuperconverterOthers
Data sent to serverNoYes
Real-time outputYes, as you typeAfter submit click
File encodingAny file typeText only
Ads and distractionsNoneBanners everywhere
Works offlineYesNo

Frequently Asked Questions

What is Base64 encoding?

Base64 is a way to represent binary data as ASCII text. It is commonly used to embed files in JSON, HTML, or email, and to pass binary data through text-only channels.

Does encoding to Base64 make data secure?

No. Base64 is an encoding, not encryption. Anyone can decode it. Use proper encryption (AES, RSA) if you need to protect sensitive data.

Why does Base64 make files about 33% larger?

Base64 encodes every 3 bytes of input into 4 ASCII characters. That 4/3 ratio results in roughly a 33% size increase, which is the trade-off for text-safe representation.

Can I encode binary files like images or PDFs?

Yes. Drop any file into the tool and it will output the full Base64 string. You can then embed it in a data URI or store it in a text-based format.

Is my data safe when using this tool?

Completely. All processing runs in your browser. No data is transmitted over the network. You can disconnect from the internet and the tool still works.

Encode or Decode Base64 Instantly

A fast, private developer utility. No signup, no ads — just paste and go.

Open Base64 Tool