Why Use Free Online Developer Tools?
You're in the middle of debugging. Your terminal spits out some garbled base64. Your API returns JSON that's impossible to read. You could fire up your IDE, install a package, then configure it. Or you could hit refresh and use a tool that's already there.
Free online developer tools save you time. They live in your browser—no installation, no dependency hell, no account needed. Whether you're reformatting JSON for the third time today, testing a regex pattern, or converting CSV to structured data, these tools handle it instantly.
AllTheTools gives you access to 13 of these utilities completely free, with zero signup. No ads tracking your inputs. No restrictions on usage. Just open a browser tab and work.
JSON Formatter: Make Messy Data Readable
JSON gets mangled. Logs compress it into one impossible line. APIs return it wrapped in extra whitespace. The JSON Formatter takes that chaos and makes it beautiful—indented, color-coded, and scannable.
Here's a real example: you paste in {"name":"alice","age":30,"email":"alice@example.com","tags":["admin","user"]} and get back formatted, colored output with proper nesting. You can spot the structure instantly.
Best for: Debugging API responses, reading log files, validating JSON structure.
Read more: JSON Formatting Guide
JSON to CSV: Convert Structured Data Fast
You've got a JSON array of user records. Your manager needs a CSV. Manually copy-pasting? That's 2026—use automation.
JSON to CSV takes an array of objects and converts it into a downloadable spreadsheet in seconds. Columns map automatically from object keys. Headers populate on the first row. No config needed.
Example: paste [{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}] and download a CSV with id and name columns populated.
Best for: Converting API data for Excel, prepping reports, exporting database results.
CSV to JSON: The Reverse Flow
Sometimes you start with a spreadsheet. Your database export. A CSV from that legacy system. You need JSON to feed into an API.
CSV to JSON reverses the process. Drop your CSV, configure which row is headers, and get back a clean JSON array. Handles quoted fields, different delimiters, the whole thing.
Real scenario: you've got a users.csv with 500 rows. Import it here. Get back perfect JSON ready to POST to your API.
Best for: Importing spreadsheet data into APIs, converting legacy exports, creating fixture files for tests.
Base64 Codec: Encode and Decode Instantly
Base64 shows up everywhere. API headers. Data URIs. Encoded credentials in logs. Sometimes you need to see what's inside. Sometimes you need to encode something to send.
The Base64 Codec handles both directions. Paste text, get the encoded version. Paste encoded data, get it decoded. Toggle between them. No guessing about what format you're working with.
Example: your OAuth token arrives base64-encoded and you need to read the payload. Paste it here, decode it, see the actual data.
Best for: Debugging authentication tokens, reading API headers, encoding sensitive data for transit.
Read more: Base64 Encoding Guide
Regex Tester: Test Patterns Against Real Text
Regex is powerful and confusing. You write a pattern. It fails on edge cases. You tweak it. You test again. This cycle repeats forever.
The Regex Tester lets you write a pattern and test it against sample text in real time. See matches highlight as you type. Try different flags (case-insensitive, global, multiline). Build confidence before shipping.
Practical example: you want to match email addresses. Type the pattern, paste a few test emails, and watch them highlight if they match.
Best for: Validating regex patterns, testing email/URL/phone formats, building search filters.
Read more: Regex Guide
URL Codec: Encode and Decode Query Strings
URL encoding turns spaces into %20 and special characters into percent-encoded chaos. You need to know what's actually in that query string. Or encode something safely to put into a URL.
The URL Codec handles both. Paste a URL or query string and see it decoded. Paste regular text and see the safe, encoded version. Copy and paste into browsers or APIs without breaking things.
Example: your API returns a URL with encoded parameters. Decode it here to see the actual values. Or encode a JSON snippet to pass as a URL parameter.
Best for: Debugging URL parameters, encoding data for GET requests, reading shortened URLs.
Color Picker: Find and Convert Color Values
Web development involves colors. Someone hands you a hex code. You need RGB. Or HSL. Or you see a color on a design and need to know its hex value.
The Color Picker converts between formats instantly. Type a hex code, see RGB and HSL versions. Need the opposite? Works backwards too. Some versions include a visual picker to grab colors directly.
Scenario: your designer says "use that blue from the mockup." You pick the color here, get the hex, drop it in your CSS.
Best for: Matching design colors, converting for different contexts, building color palettes.
Lorem Ipsum: Generate Placeholder Text Instantly
You're building a page layout. Text isn't ready. You need something to fill space so you can see how it actually looks.
Lorem Ipsum generates dummy text in whatever quantity you need. Paragraphs. Sentences. Words. Just specify the count and copy. Paste into your design, your prototype, your CMS.
Example: you need 3 paragraphs to test line height and font sizing. Generate, copy, done.
Best for: Designing layouts, testing typography, filling templates before real content arrives.
Markdown to HTML: Convert Formatting to Code
You wrote documentation in Markdown. Now you need it as HTML to embed on a website or send in an email.
Markdown to HTML does the conversion instantly. All your formatting—bold, italics, headers, links, code blocks—gets converted to proper HTML. Copy the output and paste it wherever you need it.
Real case: you've got a README with examples and you need to display it on your landing page. Convert here, paste the HTML, style with CSS.
Best for: Converting documentation, creating rich email content, preparing web content.
SQL Formatter: Clean Up Your Database Queries
SQL gets hard to read fast. Nested queries. Long WHERE clauses. Functions wrapped in functions. You need to debug it but your eyes are crossing.
SQL Formatter takes mangled queries and makes them readable with proper indentation and line breaks. Different SQL flavors get different formatting rules. Paste your mess, get back something you can actually parse.
Example: you've got a complex JOIN across 4 tables. Format it here. Now you can see the structure and spot the bug.
Best for: Debugging complex queries, preparing SQL for code review, learning how queries actually work.
How to Choose the Right Tool
Not sure which tool you need? This table breaks down what each one does and when to use it.
| Tool | Best For | Input Required | Output Type | |------|----------|----------------|------------| | JSON Formatter | Making JSON readable | JSON string or object | Formatted, colored JSON | | JSON to CSV | Converting arrays to spreadsheets | JSON array of objects | CSV file download | | CSV to JSON | Converting spreadsheets to arrays | CSV file or text | JSON array | | Base64 Codec | Encoding/decoding strings | Text or base64 | Converted string | | Regex Tester | Testing patterns against text | Regex pattern + sample text | Visual match highlights | | URL Codec | Encoding/decoding URLs | URL or plain text | Encoded/decoded string | | Color Picker | Converting color formats | Hex, RGB, or HSL code | All three formats | | Lorem Ipsum | Generating placeholder text | Number (paragraphs/sentences/words) | Plain text copy | | Markdown to HTML | Converting formatted text | Markdown syntax | HTML code | | SQL Formatter | Making queries readable | SQL query text | Formatted SQL |
What Makes AllTheTools Different
You've probably bookmarked 15 different tools across different sites. Each one with ads, some with signups, some slow to load.
AllTheTools consolidates these into one place. Everything free. Everything fast. No accounts. No tracking. No BS.
- Completely free — every tool, every feature, zero cost
- No signup required — open a tab and start working immediately
- Instant results — all processing happens in your browser, no waiting for servers
- No installation — these run in any browser, on any device, anytime
You don't have to trust us with your data because your data never leaves your browser. It's all client-side.
Get Started
Ready to streamline your development workflow? Browse the full collection of free developer tools—JSON, CSV, Base64, regex, URL encoding, and more.
Stop context-switching between tabs. All 10+ tools are here, ready to use, right now.