TV
Home All Tools Blog About

Base64 Encoder / Decoder

Encode text or data to Base64 and decode Base64 strings back to plain text instantly.

Input: Output: Overhead:

How It Works

Type or paste your text into the input area, then click Encode to convert it to Base64 or Decode to convert Base64 back to plain text. The conversion runs entirely in your browser.

Base64 is an encoding scheme that converts binary data into a text string using 64 ASCII characters. It is commonly used in emails, data URLs, API authentication tokens, and web development to transmit binary data over text-based protocols.

**What is Base64 Encoding?**

Base64 encoding takes every 3 bytes of binary data and converts them into 4 printable ASCII characters from a 64-character alphabet (A–Z, a–z, 0–9, +, /). The result is always a multiple of 4 characters, padded with `=` signs if necessary. For example, the text "Hello" becomes "SGVsbG8=" in Base64.

**Common Use Cases**

- Embedding images directly in HTML or CSS as data URLs (`data:image/png;base64,...`)
- HTTP Basic Authentication headers (`Authorization: Basic dXNlcjpwYXNz`)
- Storing binary data in JSON or XML without escaping issues
- Email attachments (MIME encoding)
- JWT (JSON Web Token) payload encoding
- Encoding credentials in environment variables

**Base64 vs Encryption**

Base64 is encoding, not encryption. It does not protect your data. Anyone who receives a Base64 string can decode it back to the original content. Never use Base64 as a security measure for sensitive information like passwords.

**URL-Safe Base64**

Standard Base64 uses `+` and `/` characters, which are not safe in URLs. URL-safe Base64 replaces `+` with `-` and `/` with `_`. This variant is used in JWTs and many web APIs. Our encoder supports both modes.

**When Decoding Goes Wrong**

Base64 strings must have a length that is a multiple of 4. If the string is malformed or has incorrect padding, decoding will fail. Our tool detects and reports these errors clearly.

**Privacy**

All encoding and decoding runs locally in your browser. Your data is never transmitted to our servers, making this tool safe for encoding sensitive configuration values and credentials.

Frequently Asked Questions

Base64 is a method of encoding binary data as ASCII text. It converts every 3 bytes of data into 4 printable characters from a 64-character alphabet.
No. Base64 is encoding, not encryption. It is easily reversible by anyone. Never use it to protect sensitive data.
Base64 works in groups of 3 bytes. If the input is not a multiple of 3 bytes, = padding is added to make the output length a multiple of 4.
Yes. Image Base64 encoding is common for embedding small images directly in HTML or CSS without a separate HTTP request.
URL-safe Base64 replaces + with - and / with _ so the encoded string can be used safely in URLs and file names without percent-encoding.