SQL Formatter

Make SELECTs and JOINs more readable with line breaks on common keywords.

Overview

SQL (Structured Query Language) was created in 1974 by Donald D. Chamberlin and Raymond F. Boyce at IBM Research, inspired by Edgar F. Codd's relational model proposed in 1970. The goal was a declarative query language: you say what you want, not how to get it. Decades later, SQL remains the most influential language in computing that almost every programmer has needed at some point — whether in a job interview or a real project. IBM shipped the System R database with SEQUEL (later renamed SQL) in the mid-1970s, and Oracle was one of the first commercial vendors. Today we have PostgreSQL, MySQL, SQLite, SQL Server, and BigQuery — each with slightly different dialects, but the core language is recognizable across all of them.

SQL readability is a recurring debate in engineering teams. A query written carelessly — `select id,name from users where active=1 and type='admin' order by name` — does the same work as a properly indented one with uppercase keywords and clauses on separate lines. But reviewing SQL in pull requests, debugging slow queries in an explain plan, or simply understanding logic someone else wrote becomes much easier when SQL is formatted. Visual indentation of JOINs, WHERE conditions, and subqueries reduces reading errors and makes logical problems easier to spot.

In practice, formatted SQL also matters for version control. When two people edit the same stored procedure or migration with different formatting preferences, diffs become polluted with cosmetic changes that obscure real ones. Teams that adopt a single formatting convention — using tools like `sqlfluff`, `pgFormatter`, or IDE-integrated formatters — have far more productive code reviews. For small projects or one-off scripts, an online formatter like this one solves the problem without any configuration.

This tool applies keyword-based formatting: line breaks before SELECT, FROM, WHERE, AND, OR, ORDER BY, GROUP BY, JOIN and their variants, with consistent indentation. It is not a full AST-aware formatter like `sqlfluff` — it does not validate syntax or suggest optimizations — but it reliably turns compact SQL into a much more readable form in seconds. For dialect-specific syntax like PostgreSQL array or JSON operators, results in proprietary sections may need manual adjustment.

Technical deep dive

Common questions summarized

  • What is this tool for?: It runs fully in your browser: useful to validate, format, or convert data in everyday development.
  • Are my inputs sent to a server?: Processing happens locally with JavaScript. We do not store what you paste into the text areas.
  • Can I use this for real production data?: Use at your own risk. For secrets (passwords, tokens), prefer controlled environments and your company policies. And always review the generated contents. Never trust blindly things you see on the internet.

Sample payload to try

  • See also the larger "Code Snippets" sample; paste this excerpt to try locally: Before and after — select id,name from users where active=1 order by name

Tool guide

  • What SQL is A declarative language to query and change data in relational databases (SELECT, INSERT, JOIN, etc.).

  • What the tool does Inserts line breaks around common keywords to make queries easier to read.

  • Why use it Read one-line SQL from logs, prepare wiki examples. Large projects usually rely on editor or CI formatters.

Code Snippets

Code example
select id,name from users where active=1 order by name

Before and after

select id,name from users where active=1 order by name

FAQ

What is this tool for?

It runs fully in your browser: useful to validate, format, or convert data in everyday development.

Are my inputs sent to a server?

Processing happens locally with JavaScript. We do not store what you paste into the text areas.

Can I use this for real production data?

Use at your own risk. For secrets (passwords, tokens), prefer controlled environments and your company policies. And always review the generated contents. Never trust blindly things you see on the internet.