Free Online Developer Tools

20 free online tools — all processing happens in your browser. No signup required, no data sent to servers.

{ } Data Format

Format, validate, and convert data between popular formats like JSON, XML, and tables. Essential for developers working with APIs and data exchange.

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JSON Formatter

Format, validate, minify and compare JSON data

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JSON to Table

Convert JSON arrays to interactive HTML tables

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JSON to XML

Convert JSON to XML and vice versa

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JSON to YAML

Convert JSON to YAML and vice versa

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XML Formatter

Format, validate, and minify XML data with syntax highlighting

🔐 Encoding

Encode and decode data using Base64, URL encoding, image-to-Base64 conversion, hex, and hash algorithms. Perfect for web development and data transmission.

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Base64 Encoder

Base64 encode and decode, with UTF-8 support

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URL Encoder

Safely encode or decode URL components with %20 or + space encoding

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Image to Base64

Convert images to Base64 strings or decode Base64 back to images

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Hash Calculator

Calculate MD5, SHA-1, SHA-256, SHA-512 hashes via Web Crypto

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Hex Converter

Convert text to hexadecimal or hex to text with UTF-8 support

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JWT Decoder

Decode JWT tokens instantly, view header, payload and signature

🔒 Security

Encrypt and decrypt data using industry-standard algorithms like AES and RSA. Also compute hash values with MD5, SHA-1, SHA-256, and more.

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AES Encryptor

Encrypt and decrypt text using AES-128/192/256 with CBC or ECB mode

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3DES Encryptor / Decryptor

Encrypt and decrypt text using 3DES with ECB, CBC, CFB, OFB modes

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RSA Encryptor

Generate RSA key pairs and encrypt/decrypt with public/private keys

Aa Text Tools

Process and analyze text data with word counter, regex tester, and other text utilities. Ideal for writers and developers.

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Word Counter

Count characters, words, sentences, and paragraphs in real-time

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Regex Tester

Test regular expressions in real-time with flag support

⏰ Time Tools

Convert between Unix timestamps and human-readable dates. Supports multiple time zones and date formats.

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Timestamp Converter

Convert Unix timestamps to readable dates

🛠 Utilities

Essential utility tools including UUID generation, hex conversion, and QR code creation. Always free, always client-side.

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UUID Generator

Generate random UUID v4 identifiers with format options (case, hyphens, wrap)

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QR Code Generator

Generate and decode QR codes. Create QR codes from URLs or text, or decode QR codes from images.

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Image to PDF

Convert images to PDF documents, support batch merge and custom page size

Why ToolZen?

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100% Private

All processing happens in your browser. No data leaves your device.

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Completely Free

No signup, no subscriptions, no hidden fees. Use all tools unlimited.

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Instant Results

No waiting for server processing. Tools respond in milliseconds.