Private browser-based code tools

Format JSON, SQL, and HTML locally. Validate payloads and compare text without uploads.

Local Code Format is a browser-based tool site for developers who need to clean JSON, check whether JSON is valid, make SQL readable, tidy HTML, or compare two versions of text without sending code to a server.

Open JSON Formatter Browse SQL Tools Read Practical Guides
Local-onlyFormatting runs in the browser, not on a remote server.
Task-firstThe tool is visible first, so you can get the job done without scrolling through filler.
Connected toolsMove from formatting to validation, SQL review, HTML cleanup, and diff checks without losing context.
Built for repeat useBookmarkable utilities for everyday debugging and cleanup work.
How to use this site
  • Open the tool that matches your job: JSON, SQL, HTML, or diff
  • Paste your code or text into the tool and get an immediate result
  • Copy the cleaned output back into your editor, ticket, or docs
  • Use a guide if you need help choosing the right tool or avoiding mistakes

What you can do here

Most visits fall into one of these jobs: make JSON readable, check whether JSON is valid, clean up SQL, tidy HTML, or compare two versions of text before you ship.

Clean messy JSON

Format API payloads, request bodies, and config snippets so they are readable and easy to copy back out.

Validate before you send

Check whether broken JSON will parse before it causes an error in a request, build step, or config file.

Review code and markup safely

Make SQL easier to read, tidy HTML without changing structure, and compare text changes without leaving the browser.

See It in Action: Code Examples

Here's how our tools transform messy code into clean, readable formats. All processing happens locally in your browser.

📊 JSON Formatting Example

Before (Minified JSON)

{"apiVersion":"v1","data":{"users":[{"id":1,"name":"Alex","email":"alex@example.com","active":true},{"id":2,"name":"Sam","email":"sam@example.com","active":false}],"total":2},"status":"success"}

After (Formatted JSON)

{
  "apiVersion": "v1",
  "data": {
    "users": [
      {
        "id": 1,
        "name": "Alex",
        "email": "alex@example.com",
        "active": true
      },
      {
        "id": 2,
        "name": "Sam",
        "email": "sam@example.com",
        "active": false
      }
    ],
    "total": 2
  },
  "status": "success"
}

Use case: Debugging API responses, cleaning config files, preparing data for documentation

🗃️ SQL Formatting Example

Before (Unformatted SQL)

SELECT u.id,u.name,u.email,o.total_amount,o.order_date FROM users u LEFT JOIN orders o ON u.id=o.user_id WHERE u.active=1 AND o.order_date>='2024-01-01' ORDER BY o.total_amount DESC LIMIT 10

After (Formatted SQL)

SELECT
  u.id,
  u.name,
  u.email,
  o.total_amount,
  o.order_date
FROM users u
LEFT JOIN orders o ON u.id = o.user_id
WHERE u.active = 1
  AND o.order_date >= '2024-01-01'
ORDER BY o.total_amount DESC
LIMIT 10

Use case: Code reviews, query optimization, sharing SQL with team members

🛡️ JSON Validation Example

Invalid JSON (Common Error)

{
  "name": "Test",
  "value": 123
  "active": true
}

❌ Error: Missing comma after "value": 123

Valid JSON (Fixed)

{
  "name": "Test",
  "value": 123,
  "active": true
}

✅ Valid JSON

Use case: API development, configuration validation, data quality checks

🌐 HTML Formatting Example

Before (Minified HTML)

<!DOCTYPE html><html><head><title>Example</title></head><body><div class="container"><h1>Hello</h1><p>This is a test</p></div></body></html>

After (Formatted HTML)

<!DOCTYPE html>
<html>
<head>
  <title>Example</title>
</head>
<body>
  <div class="container">
    <h1>Hello</h1>
    <p>This is a test</p>
  </div>
</body>
</html>

Use case: Debugging markup, code reviews, learning HTML structure

💡 How to Use These Examples

1. Copy and Test

Copy the "Before" examples into our tools to see the transformation instantly.

2. Learn Patterns

Study the formatting patterns to understand how our tools structure code.

3. Apply to Your Code

Use the same principles to format your own JSON, SQL, HTML, and other code.

Remember: All processing happens locally in your browser. Your code never leaves your computer.

Pick your tool

Use one of these pages to get straight into the task without creating an account or uploading code elsewhere.

Need help choosing the right page?

If you are not sure whether you should format first, validate first, or open a more specific page, start with one of these short paths.

JSON cleanup and validation

Use these pages when you need to fix broken payloads, clean a response body, or make JSON readable before sharing it with a teammate.

SQL, HTML, and diff review

These pages are for the jobs that happen right after cleanup: making queries readable, inspecting markup, and spotting text changes before you ship them.

Read a guide when you need the next step

These guides are here for the questions that usually come right after opening a tool: what to use first, how to handle sensitive code safely, and how to avoid breaking markup or queries.

Your code stays in your browser while you work.

Use Local Code Format when you want to clean JSON, validate a payload, format SQL, inspect HTML, or compare text changes without pasting sensitive material into a random third-party tool. Open the tool, paste what you have, get the result, and move on.