Unix Timestamp ↔ Date Converter
Convert Unix timestamps into human-readable date and time
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Why Developers Need Free Online Tools Today
I created this suite of free online developer tools because I know how painful everyday coding tasks can be when you do not have the right utilities at hand. Instead of juggling multiple desktop apps, heavy IDE extensions, or unreliable online services, you can paste your code directly into the browser and instantly beautify, minify, validate, or compare it.
By running everything entirely in your browser, these developer utilities give you three things every coder wants:
- Speed: No waiting for uploads or round-trips to a server.
- Privacy: Your code never leaves your device, keeping sensitive logic and data safe.
- Reliability: The output is consistent every time, following clean formatting rules.
The goal is simple: to boost your productivity without sacrificing privacy, performance, or peace of mind.
What You Can Do With Our Developer Tools
This is more than just a JSON formatter or CSS minifier. The CodeForGeek developer tools hub is a complete collection of free browser-based utilities designed for developers, students, engineers, and anyone working with data, code, or text. Here is what you can actually do here:
Format and Beautify Code
Readable code saves time. With tools like the JavaScript Formatter, PHP Beautifier, CSS Prettify, SQL Formatter, HTML Prettify, and JSON Prettify, you can take messy one-liners or minified blobs and instantly convert them into well-indented, human-friendly scripts.
Minify for Faster Websites
Need smaller files for better performance? Use HTML Minify, CSS Minify, JavaScript Minify, PHP Minify, SQL Minify, XML Minify, and JSON Minify. These tools strip whitespace, comments, and extra characters to reduce file size, cut load times, and improve SEO metrics like Core Web Vitals.
Compare Files Side by Side
Spot differences instantly using the Text Compare Tool or Compare JSON Tool. Whether you are debugging API responses, reviewing config files, or checking changes between two logs, these tools highlight differences clearly without needing a local diff app.
Test and Debug Faster
Interactive utilities like the Online Regex Tester and Debugger help you experiment with regular expressions safely. The REST API Tester lets you send requests and inspect responses right in the browser. The JWT Decoder reveals the contents of JSON Web Tokens instantly for debugging authentication flows.
Generate and Convert Data
Working with data formats? You can:
- Convert JSON to YAML, JSON to XML, or XML to JSON in seconds.
- Convert CSV to JSON, CSV to TSV, or CSV to Excel for data pipelines.
- Switch between Markdown and HTML in either direction.
- Convert between RGB and Hex colors for web design.
- Turn Decimal to BCD, BCD to Decimal, Gray Code to Decimal, or Decimal to Gray Code when working with hardware logic.
Encode and Decode Easily
Encoding utilities help when working with APIs, URLs, and data transfer:
- Base64 Encoder/Decoder for text or files.
- URL Encoder/Decoder for safe query strings.
- UTF-8 Encode/Decode to handle text correctly.
- IDN Encode/Decode for internationalized domain names.
Convert Units and Values
Designers and frontend devs can use the PX to REM Converter and REM to PX Converter for responsive web design. Working in electronics? The XOR Calculator makes Boolean operations easy.
Generate Strong Passwords
The Password Generator creates strong, random, and customizable passwords instantly, complete with entropy estimates. Perfect for securing accounts, APIs, and databases.
Supported File Types And Formats
This hub is not limited to just JSON or HTML. The tools here cover a wide range of developer file types, encodings, and data formats that you work with daily:
- JSON: Prettify messy API responses, minify compact payloads, convert JSON to YAML, TSV, XML, or Excel, and compare JSON files side by side.
- HTML: Beautify template code, clean up messy CMS output, convert HTML to Markdown, or shrink production HTML files.
- CSS: Use CSS beautifier to format stylesheets or CSS minify to reduce file size for faster websites.
- JavaScript: Beautify code for debugging, minify before shipping, or obfuscate for lightweight protection. Regex testing and JWT decoding add extra support for debugging scripts.
- PHP: Format server-side scripts or minify includes for better performance.
- SQL: Tidy up complex queries with the SQL formatter, or compact them for deployment with SQL minify.
- XML: Beautify XML configuration files, compress them with XML minify, or convert XML to JSON for API pipelines.
- Text: Compare logs, drafts, or code snippets with the text compare tool.
- CSV & TSV: Convert CSV to JSON, TSV, or Excel. Convert JSON back to CSV or TSV for quick dataset handling.
- Markdown: Convert Markdown to HTML for publishing or HTML to Markdown for documentation.
- Encodings: Encode or decode Base64, URL strings, UTF-8 text, or IDN domain names with one click.
- Color Codes: Convert RGB to Hex or Hex to RGB when designing for the web.
- Timestamps: Instantly convert Unix timestamps to human-readable dates and back.
- Binary/Logic Codes: Convert Decimal to BCD, BCD to Decimal, Gray Code to Decimal, and Decimal to Gray Code. Use the XOR calculator for simple logic checks.
- Passwords: Generate secure passwords with entropy estimation to protect accounts and APIs.
- APIs: Test REST API endpoints in your browser without external software.
Benefits Of Using These Online Developer Tools
When you are working with JSON responses, HTML templates, CSS files, SQL queries, or even Markdown documentation, every second spent formatting or debugging code slows down your workflow. That is why developers turn to free online developer tools: they are fast, reliable, and private. Here are the biggest benefits you get by using them:
Save Time With Instant Formatting And Minification
Instead of manually fixing indentation or removing whitespace, these tools give you one-click code formatting and minification. You paste your code, hit format or minify, and get consistent output in seconds. This is especially useful when working with JSON beautifiers, SQL formatters, HTML prettifiers, or CSS minifiers.
Improve Website Performance And SEO
Minified HTML, CSS, and JavaScript reduce file size, cut bandwidth usage, and improve Core Web Vitals scores like Largest Contentful Paint (LCP). Faster load times directly impact SEO rankings and user experience. Using tools like the JavaScript minifier or CSS compressor makes your site lighter and more search-friendly.
Ensure Consistency Across Teams
Clean and consistent formatting is crucial for teams. A PHP beautifier, SQL formatter, or JSON prettify tool ensures everyone sees the same indentation and style rules, reducing confusion during code reviews and version control.
Debug And Test With Zero Setup
Tools like the online regex tester, JWT decoder, and REST API tester let you experiment and debug instantly without firing up a local environment. This lowers friction when troubleshooting regex patterns, authentication tokens, or API payloads.
Work Safely With Local Processing
All tools run directly in your browser using JavaScript or WebAssembly. That means your code never leaves your computer. This makes them safe for handling sensitive JSON payloads, SQL queries, or API tokens without risking a leak to external servers.
Access From Anywhere, On Any Device
Because they are browser-based, these tools work on Windows, macOS, Linux, and mobile devices. Whether you are coding at your desk, on a train, or using a tablet in a meeting, you can still format, minify, or convert code instantly.
Convert Between Formats Without Hassle
Instead of writing custom scripts for quick conversions, you can use tools like CSV to JSON converter, Markdown to HTML converter, XML to JSON converter, or RGB to Hex converter. This saves effort on routine tasks and avoids dependency on heavy IDE plugins.
No Installation, No Accounts, No Ads
Unlike desktop software or SaaS subscriptions, you do not need to install anything or create an account. You just load the page, paste your code, and copy the result. The workflow is simple, distraction-free, and accessible for students, professionals, and beginners alike.
Free Forever And Continuously Updated
All developer tools here are free, updated regularly, and designed with developer feedback in mind. Whether you are using the password generator, Unix timestamp converter, or Base64 encoder/decoder, you can rely on them without worrying about hidden fees or limitations.
Online Tools vs Desktop Software: Which Is Better?
| Feature / Benefit | Online Developer Tools (Browser-Based) | Desktop Software / IDE Plugins |
|---|---|---|
| Installation | No installation needed, runs in browser | Requires setup, downloads, updates |
| Accessibility | Works on any device (PC, Mac, Linux, mobile) | Limited to installed machine |
| Speed | Instant results with one click | Can be slower, depends on system load |
| Privacy | Runs locally in browser, no uploads | Local processing, but some plugins send telemetry |
| Formats Supported | JSON, HTML, CSS, JS, PHP, SQL, XML, CSV, TSV, Markdown, Encodings | Often limited to the IDE’s supported languages |
| Conversion Utilities | CSV ↔ JSON, Markdown ↔ HTML, RGB ↔ Hex, URL/Base64/UTF-8 encoding/decoding | Rarely included, usually requires extra plugins |
| Cross-Platform | Works in Chrome, Firefox, Safari, Edge | OS or IDE-specific |
| Cost | Free to use, no subscription | Some paid software or plugin costs |
| Maintenance | Updated centrally, always latest version | Needs manual updates, compatibility issues |
| Learning Curve | Simple UI, beginner-friendly | Can be complex, IDE-specific knowledge needed |
Frequently Asked Questions (FAQs)
What are online developer tools?
Online developer tools are browser-based utilities that let you format, minify, compare, encode, decode, and convert code or data without installing software. They support JSON, HTML, CSS, JavaScript, PHP, SQL, XML, and more.
Are online developer tools safe to use?
Yes. The tools run entirely in your browser using JavaScript or WebAssembly, meaning your code never leaves your device. This makes them safe for working with sensitive JSON payloads, SQL queries, or API tokens.
Do I need to install anything to use these tools?
No. All tools work directly in your browser. Just paste or upload your code, click the action button, and copy the result. No installation, no plugins, and no extensions required.
Which file formats are supported by these tools?
The supported formats include JSON, HTML, CSS, JavaScript, PHP, SQL, XML, CSV, TSV, Markdown, RGB/Hex colors, Unix timestamps, Gray Code, BCD, and plain text. Encoding and decoding tools also support Base64, URL strings, UTF-8, and IDN.
Can I minify and beautify code online for free?
Yes. You can minify HTML, CSS, JavaScript, PHP, SQL, XML, and JSON to shrink files, or beautify them back to readable, indented code. Both tasks are free and unlimited.
Does minifying HTML, CSS, and JS improve SEO?
Yes. Minification reduces file size and improves page load speed, which positively affects Core Web Vitals and SEO rankings. Faster websites perform better in search engines and provide a better user experience.
Can I use these tools on mobile devices?
Yes. All tools work in mobile browsers like Chrome, Safari, and Firefox. While large files are easier to process on desktop, mobile devices can handle most conversions and formatting.
Do these tools work offline?
Most tools continue to work offline once the page is loaded, because the logic runs locally in your browser. Some converters that rely on libraries may need an internet connection to load initially.
Can I compare two files online?
Yes. Tools like the Text Compare Tool and JSON Compare let you paste two blocks of code or text side by side and highlight differences instantly.
What is the advantage of using an online regex tester?
An online regex tester helps you experiment with regular expressions without running code in an IDE. You can paste text, write a regex, set flags, and instantly see matches and capture groups highlighted.
What does the JWT decoder tool do?
The JWT decoder takes a JSON Web Token and shows its header, payload, and signature in a readable format. It is useful for debugging authentication flows and API integrations.
How does the password generator work?
The online password generator creates random, secure passwords using lowercase, uppercase, numbers, and symbols. It also estimates entropy to show how strong the password is against brute-force attacks.
Are these tools really free?
Yes. All developer tools on this site are free to use with no sign-ups and no hidden paywalls. You can bookmark them and use them anytime.
Can these tools replace desktop software?
For many tasks, yes. Online developer tools are faster for quick formatting, minification, or conversions. Desktop IDEs are still better for large-scale projects, but for everyday developer tasks, online tools are more efficient.
Thank You Note
I know if you made it this far, you probably really needed these tools. I built this collection of free online developer tools to save time, reduce frustration, and make coding tasks more reliable. Whether you used the JSON formatter, CSS minifier, REST API tester, or any of the other utilities here, I hope it helped you get your job done faster.
I keep building new tools every week, some small and some surprisingly powerful. You can check out all our free tools here and make sure to bookmark CodeForGeek so you never lose us.
If you have an idea for improvement or something is not working right, just email me at [email protected]. I read every message, and if your suggestion makes sense, I will add it to the next update.
Thanks for sticking around till the end. Now go try out your favorite tool before you forget why you came here.