Free SQL Formatter & Beautifier

Why Format SQL?

SQL is one of the most widely written programming languages in the world — used by developers, data analysts, DBAs, and business intelligence professionals every day. But unlike Python or JavaScript, SQL queries are frequently written in a hurry, copied from tools that output dense single-line queries, or generated by ORMs that produce compact but unreadable strings. The result is SQL that technically works but is nearly impossible to review, debug, or maintain. A simple SELECT statement with several JOINs, subqueries, and a complex WHERE clause can become completely illegible when crammed onto one line.

Formatting SQL — adding consistent indentation, capitalising keywords, and separating clauses onto their own lines — transforms unreadable queries into self-documenting code. A well-formatted SQL query makes it immediately clear what data is being selected, which tables are joined and how, what filters are applied, and how results are grouped or ordered. This reduces debugging time, improves code review quality, and makes it significantly easier to spot logical errors like incorrect JOIN conditions or missing parentheses.

SQL Formatting Best Practices

There is no single universal SQL style guide, but certain conventions are widely adopted across the industry:

• Uppercase reserved keywords: Capitalising SQL keywords — SELECT, FROM, WHERE, JOIN, ON, AND, OR, GROUP BY, ORDER BY, HAVING, LIMIT — clearly distinguishes them from table names, column names, and aliases, which are typically lowercase or mixed case.
• One clause per line: Each major clause (SELECT, FROM, WHERE, GROUP BY, ORDER BY, LIMIT) starts on a new line. For SELECT with multiple columns, put each column on its own line with consistent indentation.
• Indent sub-clauses and subqueries: Conditions in WHERE, clauses in ON, and subqueries should be indented relative to their parent clause, revealing the logical nesting structure of the query.
• Align AND/OR operators: In complex WHERE clauses with multiple conditions, align AND and OR at the same indentation level to make the logical structure explicit.
• Comment complex logic: Use -- single-line comments or /* */ block comments to explain non-obvious JOIN conditions, business logic filters, or performance-related hints.
• Explicit JOIN types: Always specify the JOIN type (INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL OUTER JOIN) rather than relying on the default INNER JOIN. Explicit types make query intent clear to anyone reading it later.

SQL Dialect Differences

While the SQL standard provides a common foundation, each major database system has significant dialect differences that affect syntax and formatting choices:

• MySQL: Uses backticks to quote identifiers (`table_name`), supports LIMIT for row limiting, and has a REPLACE INTO upsert syntax. MySQL 8.0 added window functions and CTEs.
• PostgreSQL: Uses double quotes for identifiers ("table_name"), is fully ANSI SQL compliant, supports a rich type system, and has powerful array and JSON operators. Supports ILIKE for case-insensitive matching.
• SQL Server: Uses square brackets for identifiers ([table_name]), uses TOP n instead of LIMIT, and has T-SQL extensions including stored procedures, triggers, and a rich set of built-in functions.
• Generic SQL: The ANSI SQL standard syntax that works across most databases — useful when writing cross-database compatible queries or documentation.

Common SQL Formatting Rules

The formatter in this tool applies the following rules: SQL keywords are uppercased (SELECT, FROM, WHERE, JOIN, etc.); each major clause begins on a new line; JOIN conditions are indented on the line following the JOIN keyword; columns in SELECT statements are each on their own line with a leading comma or trailing comma depending on preference; nested subqueries are indented relative to the outer query; and trailing whitespace is removed from all lines.

Frequently Asked Questions

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