Are all these developer tools free?

Yes — every tool is completely free with no sign-up, no rate limits, and no subscription. All processing happens in your browser, so there are no server costs.

Do the tools send my code or data to a server?

No. All processing happens in your browser using JavaScript. No input is transmitted anywhere. We cannot see or access your code, API keys, tokens, or data.

Can I use the JSON formatter for large JSON files?

Yes. The tool runs entirely in your browser, so performance depends on your device. Files up to a few MB process instantly on modern hardware. Very large files (10 MB+) may be slow on older devices.

Does the JWT decoder verify the signature?

No — it decodes and displays the header and payload for inspection only. Signature verification requires the secret key and must be done server-side or with a library that has access to your secret.

What regex flavor does the Regex Tester use?

JavaScript (ECMAScript) regex, which is the standard for browser-based tools. Flags g (global), i (case-insensitive), m (multiline), and s (dotAll) are supported. PCRE-specific features like lookbehind may have limited support.

Can I use these tools offline?

Once the page is loaded, most tools work without an internet connection since all logic runs in-browser. Tools that fetch external data (like IP lookup or DNS resolver) require a connection.

How do I format minified JSON?

Use the JSON Formatter tool. Paste your minified JSON and the tool will parse it, validate syntax, and display it with proper indentation and syntax highlighting. It also shows errors if the JSON is malformed.

What is Base64 encoding used for?

Base64 converts binary data into ASCII text so it can be transmitted over text-based protocols like HTTP headers, JSON, or email. Common uses include embedding images in HTML/CSS and encoding authentication credentials.

Can I generate UUIDs in bulk?

Yes — use the UUID Generator tool. It generates cryptographically secure Version 4 UUIDs using the browser's crypto.randomUUID() API. You can generate multiple UUIDs at once and copy them as a list.

How do I test a regular expression?

Use the Regex Tester tool. Enter your regex pattern, paste your test string, and see live matches highlighted in the text. The tool shows all matches, capture groups, and whether the pattern is valid.

Free Online Developer Tools

JSON, JWT, Base64, regex, UUID, SQL, CSS, and more — all running privately in your browser.

Getting Started with Developer Tools

Every developer tool runs entirely in your browser using JavaScript. Paste your code, get instant results — no uploads, no server processing, no account required. Your code and data never leave your device.

📋 Data Format

• JSON Formatter — Pretty print
• XML Formatter — Indentation
• SQL Formatter — Query beautify
• YAML Validator — Syntax check

🔐 Encoding

• Base64 Encoder — Text to Base64
• JWT Decoder — Inspect tokens
• URL Encoder — Safe URLs
• Hash Generator — MD5/SHA

🛠️ Utilities

• Regex Tester — Pattern match
• UUID Generator — Unique IDs
• Timestamp Converter — Unix time
• CSS Minifier — Compress code

JSON Formatter

Popular

Format, validate, and minify JSON with syntax highlighting and error detection

JWT Decoder

Popular

Decode and inspect JSON Web Token headers, payloads, and expiry claims

Base64 Encode / Decode

Popular

Encode text or files to Base64 and decode Base64 strings back to plain text

Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa, in any timezone

Regex Tester

Popular

Test and debug regular expressions with live match highlighting and group capture

UUID Generator

Generate RFC-compliant UUIDs (v4) in bulk with one-click copy

SQL Formatter

Format and beautify SQL queries with configurable indentation and keyword casing

CSS Minifier

Minify CSS by removing whitespace, comments, and redundant rules to reduce file size

Word Counter

Popular

Count words, characters, sentences, paragraphs, and reading time in any text

Remove Duplicates

Remove duplicate lines from any list — case sensitive or insensitive, with sort options

Case Converter

Popular

Convert text between camelCase, PascalCase, snake_case, kebab-case, UPPER_CASE, and more

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text by words, sentences, or paragraphs

Your Privacy Is Guaranteed

Unlike most online tools, Toolivon processes everything directly in your browser using the Web APIs built into Chrome, Firefox, Safari, and Edge.

✓Your files are never uploaded to any server
✓Nothing is stored after you close the tab
✓No account or email is required
✓Works offline once the page is loaded
✓GDPR-friendly by design — no data leaves your device

Learn how it works →

Frequently Asked Questions

Last updated: August 6, 2026

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Free Online Developer Tools

Getting Started with Developer Tools

📋 Data Format

🔐 Encoding

🛠️ Utilities

Developer Tool List

JSON Formatter

JWT Decoder

Base64 Encode / Decode

Timestamp Converter

Regex Tester

UUID Generator

SQL Formatter

CSS Minifier

Word Counter

Remove Duplicates

Case Converter

Lorem Ipsum Generator

Your Privacy Is Guaranteed

Frequently Asked Questions

Are all these developer tools free?

Do the tools send my code or data to a server?

Can I use the JSON formatter for large JSON files?

Does the JWT decoder verify the signature?

What regex flavor does the Regex Tester use?

Can I use these tools offline?

How do I format minified JSON?

What is Base64 encoding used for?

Can I generate UUIDs in bulk?

How do I test a regular expression?

Related Tool Categories

Free Online Developer Tools

Getting Started with Developer Tools

📋 Data Format

🔐 Encoding

🛠️ Utilities

Developer Tool List

JSON Formatter

JWT Decoder

Base64 Encode / Decode

Timestamp Converter

Regex Tester

UUID Generator

SQL Formatter

CSS Minifier

Word Counter

Remove Duplicates

Case Converter

Lorem Ipsum Generator

Your Privacy Is Guaranteed

Frequently Asked Questions

Are all these developer tools free?

Do the tools send my code or data to a server?

Can I use the JSON formatter for large JSON files?

Does the JWT decoder verify the signature?

What regex flavor does the Regex Tester use?

Can I use these tools offline?

How do I format minified JSON?

What is Base64 encoding used for?

Can I generate UUIDs in bulk?

How do I test a regular expression?

Related Tool Categories