Developer Tool
Base64 Encoder & Decoder 🔐
Encode any text or file to Base64, or decode Base64 strings back to plain text. Fast, private, and fully browser-based — no data is sent to any server.
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📋 How To Use
1
Select Encode or Decode. Use the toggle at the top to switch between encoding plain text to Base64 and decoding a Base64 string back to its original text.
2
Paste your input. For encoding: paste any plain text, JSON, HTML, or code. For decoding: paste the Base64 string you want to convert back — it typically contains only letters, numbers, +, /, and = characters.
3
Click Encode or Decode. The result appears instantly in the output box with stats showing input size, output size, and encoding ratio.
4
Copy or swap. Copy the result to clipboard with one click, or use “Send to Decoder/Encoder” to instantly move the output into the other tool for chained operations.
⚙️ How Base64 Works
What is Base64?
Base64 is an encoding scheme that converts binary data into a string of 64 safe ASCII characters (A–Z, a–z, 0–9, +, /). It is not encryption — it is purely a representation format.
Size Increase
Base64 encoded data is approximately 33% larger than the original. Every 3 bytes of input becomes 4 characters of Base64 output. This is the standard overhead of the encoding.
Common Uses
Embedding images in CSS/HTML (data URIs), encoding binary data in JSON APIs, passing data in URLs safely, storing binary data in databases, and transmitting data in email (MIME encoding).
Is It Secure?
No. Base64 is not encryption — anyone can decode it. It is simply a way to represent binary data as text. Never use Base64 to protect sensitive data like passwords or personal information.
❓ Frequently Asked Questions
Base64 is used whenever binary data needs to be stored or transmitted as text. The most common uses are: embedding images directly in HTML or CSS using data URIs (data:image/png;base64,…), encoding binary payloads in REST API responses (which are JSON text), email attachments (MIME), HTTP Basic Authentication headers, and encoding cryptographic keys and certificates (PEM format).
No — and this is a very important distinction. Base64 is an encoding scheme, not encryption. Anyone who sees a Base64 string can instantly decode it with any Base64 decoder tool. It provides no security or confidentiality. If you need to protect data, use proper encryption like AES-256. Base64 simply makes binary data safe for text-based systems — nothing more.
Base64 processes data in groups of 3 bytes, producing 4 characters per group. When the input length is not a multiple of 3, padding characters (=) are added to make the output length a multiple of 4. One = means 1 byte of padding was needed; == means 2 bytes. This padding ensures the decoder knows exactly how many bytes the original data contained.
Yes. This tool uses UTF-8 encoding before Base64 conversion, which means it correctly handles any Unicode text including Arabic, Chinese, Japanese, Korean, emojis, and special symbols. The resulting Base64 string can be decoded back to the original UTF-8 text without any character loss.
Standard Base64 uses only: uppercase A–Z (26 chars), lowercase a–z (26 chars), digits 0–9 (10 chars), plus (+), forward slash (/), and equals (=) for padding — 65 characters total. URL-safe Base64 replaces + with – and / with _ to make the string safe for use in URLs and file names without percent-encoding. If you see characters outside this set in a supposed Base64 string, the decoder will return an error.
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Found a Bug or Have a Suggestion?
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