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GenTradeTools

Base64 Encoder & Decoder

Encode text to Base64 or decode Base64 strings with real-time validation and file support

Standard Base64
Plain Text Input0 B
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Base64 Output
0 B
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Quick Examples

Features

Bidirectional

Encode plain text or decode Base64 strings instantly

URL-Safe Format

Support for URL-safe Base64 with - _ instead of + /

Auto Convert

Real-time conversion as you type with auto-convert mode

Image Preview

Automatic image preview when decoding Base64 images

Data URI Copy

One-click copy as complete data URI for embedding

Line Break Options

Add line breaks at 64, 76 (MIME), or 80 characters

File Support

Encode any file to Base64 or upload text files

MIME Detection

Auto-detect or manually set MIME type for data URIs

Statistics

Live size tracking and encoding overhead calculation

Monaco Editor

VS Code-powered editing with syntax highlighting

Real-time Validation

Instant feedback on Base64 string validity

Client-Side

100% browser-based, your data never leaves

Developer Tools

What is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that represents binary data using 64 ASCII characters. It's commonly used to encode data that needs to be stored or transferred over media designed for text, ensuring the data remains intact without modification during transport.

This tool runs entirely in your browser—no data is transmitted to any server. Whether you're encoding images for data URIs, handling API authentication tokens, or debugging encoded strings, your data stays completely private.

How to Use

01

Choose Mode

Select Encode or Decode

02

Enter Data

Paste text or upload a file

03

Get Result

Click process, then copy or download

Common Use Cases

Data URIs

Embed images, fonts, or other assets directly in CSS or HTML without external file requests.

API Authentication

Encode credentials for HTTP Basic Authentication headers or JWT token payloads.

Email Attachments

MIME encoding for email attachments ensures binary files survive text-only transport.

Data Storage

Store binary data in JSON, XML, or databases that only support text strings.

Standard vs URL-Safe Base64

Standard Base64
Characters

A-Z, a-z, 0-9, +, /

Padding

Uses = padding

Best For

Email, general encoding

Example

SGVsbG8rV29ybGQ=

URL-Safe Base64
Characters

A-Z, a-z, 0-9, -, _

Padding

No padding

Best For

URLs, filenames, APIs

Example

SGVsbG8tV29ybGQ

Field guide to Base64 workflows

Deep dive into why the Base64 tool exists, how to avoid data mishandling, and the compliance stories you can tell once encoding is audited.

Problem framing

Every integration engineer eventually pastes a token, webhook payload, or inline image into a chat thread and wonders whether the content now lives forever on an external server. The Base64 Encode/Decode tool eliminates that anxiety by processing everything in-browser. No uploads, no logging. That single promise lets regulated teams transform secrets, share them with peers, and move on without spinning up a local script.

Encoding responsibly

Base64 is not encryption. It is a transport-friendly wrapper that keeps binary blobs intact when moving through systems that only accept ASCII. This article treats encoding as a reliability step, not a security guarantee. When you paste a PDF or JWT into the encoder, the output remains legible to anyone with the decode button, so pair the workflow with TLS links or encrypted chat.

Typical use cases

  • Embed small SVG or PNG assets directly into CSS without touching the filesystem.
  • Inspect email attachments that arrive as Base64 blocks inside MIME bodies.
  • Debug OAuth signatures by decoding headers and verifying claims.
  • Share cloud configuration templates with teammates who cannot access your repo yet.

Safeguards inside the tool

The component auto-detects whether the pasted text looks like Base64 and flips the action buttons accordingly. It surfaces character counts, byte sizes, and padding details so you can catch truncation immediately. If the decoder encounters invalid characters, the alert banner explains which index broke the parser, making it easier to fix copy-paste accidents.

Operational stories

Support teams often need to confirm whether a customer-provided blob is complete before forwarding to engineering. Instead of saving that snippet to disk (risky on shared laptops), they paste it here, decode, and preview the underlying JSON or binary signature. Compliance officers appreciate the traceability notes: every article we publish reinforces that no network request fires during encoding, satisfying internal audits.

Best practices checklist

  1. Trim whitespace before sharing encoded strings; trailing line breaks can invalidate webhook signatures.
  2. Keep encoded attachments under 1 MB when embedding into HTML emails to avoid bloating message size.
  3. Document why you encoded something in the first place; future maintainers should not guess whether a string is hashed, encrypted, or merely Base64.
  4. Rotate secrets even if the encoded version only lived in this tool; encoding alone is not a security boundary.

Beyond the basics

Because the tool is pure frontend, you can run it offline after a single load. Teams traveling to restricted environments download the page, disconnect, and continue transforming payloads on airplanes or in secure labs. When you are ready for automation, mirror the exact behavior via the open-source helper in '@/lib/base64Utils' so CI pipelines and human reviewers share the same logic.

FAQ

Is Base64 encryption?

No. Base64 is encoding, not encryption. Anyone can decode Base64 strings. Never use it to protect sensitive data—use proper encryption instead.

Why does Base64 increase file size?

Base64 uses 4 characters to represent every 3 bytes of data, resulting in approximately 33% size increase. This is the tradeoff for ASCII-safe transport.

When should I use URL-safe Base64?

Use URL-safe Base64 when the encoded string will appear in URLs, query parameters, filenames, or anywhere + and / characters could cause issues.

Is my data secure?

Yes. This tool runs entirely in your browser. No data is transmitted to any server—your encoding and decoding happens 100% locally.

100% Client-Side·No Data Transmission·Privacy First