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Base64 Encoder / Decoder

Encode text to Base64 and decode Base64 to text instantly

Text / Input

Base64 Output

File to Base64

Drag & drop a file here or click to browse

Max recommended: 5MB

How Base64 Encoding Works

Base64 encoding converts binary data into a text representation using 64 ASCII characters. It is commonly used to embed images in HTML/CSS, transmit data in URLs, and encode email attachments.

Use Cases

Important Note

Base64 is NOT encryption. It provides no security and can be trivially decoded by anyone.

Frequently Asked Questions

What is Base64 encoding?
Base64 is a binary-to-text encoding scheme using 64 printable ASCII characters. It is used for embedding images, transmitting data over text-based protocols, and encoding email attachments.
Is Base64 encryption?
No, Base64 is NOT encryption. It is a reversible encoding. Anyone can decode it. Never use Base64 to protect sensitive data.
Why does Base64 increase file size?
Base64 increases data size by ~33% because 3 bytes of binary data require 4 ASCII characters to represent.
Can I convert files to Base64?
Yes, drag and drop a file or use the file picker. The file contents will be converted to a Base64 string.

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What is Base64 encoding?

Base64 encoding represents binary data as 64 printable ASCII characters so it can travel safely through text-only channels; it is an encoding, not encryption, and anyone can decode it.

SnoopTool encodes and decodes in the browser with full UTF-8 support, so accented characters and emoji survive the round trip. Encoded output is about 33% larger than the input.

Base64 Encoder / Decoder: key facts

Reference facts for the SnoopTool Base64 Encoder / Decoder, a free browser-based tool.
AlphabetA–Z, a–z, 0–9, + and /, with = as padding
Size overheadRoughly +33% (3 bytes become 4 characters)
SecurityNone — Base64 is reversible by anyone; it is not encryption
URL-safe variantReplaces + with - and / with _ (RFC 4648 §5)
Common usesData URIs, email attachments, JWT segments, API payloads

Why use the SnoopTool Base64 Encoder / Decoder?

How to use the Base64 Encoder / Decoder (step by step)

  1. Pick encode or decode. Select the direction you need.
  2. Paste your input. Drop in plain text or a Base64 string.
  3. Run it. The converted output appears immediately.
  4. Copy the result. Copy the output — nothing is sent to a server.

Related free tools on SnoopTool

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