SQL Formatter & Beautifier Online

SQL Dialects Supported

How SQL Formatting Works

A proper SQL formatter does not use simple find-and-replace. It works in three stages:

1. Tokenization -- The raw SQL string is split into tokens: keywords, identifiers, operators, literals, and comments. String literals and comments are preserved verbatim so keywords inside strings are never modified.
2. Structure analysis -- Tokens are grouped into clauses (SELECT, FROM, WHERE, JOIN, etc.) and nesting levels (subqueries, function calls, CASE expressions). This determines where to insert line breaks and indentation.
3. Rendering -- The structured token tree is converted back to text with the selected formatting rules applied: keyword case, indent width, line breaks between clauses, and alignment.

This is why a parser-based formatter handles complex SQL correctly -- it understands structure, not just patterns. A regex-based approach would break on subqueries, string literals containing keywords, nested function calls, and CTE expressions.

Formatting vs. Linting vs. Optimization

• Formatting changes how SQL looks. It never changes behavior.
• Linting checks for potential issues like missing aliases, ambiguous column references, or deprecated syntax.
• Optimization rewrites the query logic for better performance (adding indexes, restructuring joins, etc.).

This tool does formatting only. The query you get back runs identically to the one you put in.

SQL Formatting Best Practices

Keyword Case Convention

The dominant industry convention is uppercase keywords. This creates a visual separation between SQL structure (SELECT, WHERE, JOIN) and your data names (users, order_total, created_at). Some modern teams prefer lowercase for consistency with programming language conventions. Either works -- consistency across your codebase matters more.

SELECT
  u.name,
  u.email,
  COUNT(o.id) AS order_count
FROM users u
JOIN orders o
  ON u.id = o.user_id
WHERE u.active = 1
GROUP BY u.name, u.email
HAVING COUNT(o.id) > 5
ORDER BY order_count DESC;

select
  u.name,
  u.email,
  count(o.id) as order_count
from users u
join orders o
  on u.id = o.user_id
where u.active = 1
group by u.name, u.email
having count(o.id) > 5
order by order_count desc;

Indentation Rules

• Major clauses (SELECT, FROM, WHERE, GROUP BY, ORDER BY) start at the left margin or at the current nesting level.
• Column lists and conditions are indented one level deeper than their clause.
• Subqueries are indented one level deeper than the surrounding query.
• JOIN conditions (ON) are indented under the JOIN keyword.
• CASE expressions indent WHEN/THEN/ELSE under CASE.

Line Breaks

• Put each major clause on its own line.
• One column per line in SELECT lists when there are more than 2-3 columns.
• AND/OR on new lines in WHERE clauses, indented under WHERE.
• Each JOIN on its own line with its ON condition below it.

Naming Conventions

• Use snake_case for table and column names (not camelCase).
• Table names: singular or collective nouns (user or staff, not users_table).
• Suffix conventions: _id, _at (timestamps), _count, _total, _name.
• Avoid prefixes like tbl_ or sp_.

Frequently Asked Questions

What does a SQL formatter do?

A SQL formatter restructures raw or compressed SQL with consistent indentation, line breaks, and keyword casing. It makes queries easier to read, review, and debug without changing what the query does.

Does formatting SQL change query results?

No. SQL formatting is cosmetic. The database ignores whitespace, indentation, and keyword case. Your formatted query runs identically to the original.

Should SQL keywords be uppercase?

Uppercase keywords (SELECT, FROM, WHERE) is the most common convention because it visually separates SQL structure from column and table names. Some teams prefer lowercase. The key is consistency across your project.

What is the best indent size for SQL?

2 spaces and 4 spaces are both common. Most style guides recommend 2-4 spaces. Tabs are less common in SQL but work fine if your team uses them. Match your project standard.

Can this formatter handle subqueries and CTEs?

Yes. This tool uses a parser-based formatter that understands SQL structure including nested subqueries, CTEs (WITH clauses), CASE expressions, window functions, and complex JOIN conditions.

Why does the formatter not fix my SQL error?

A formatter restructures layout, not logic. If your SQL has syntax errors (missing parenthesis, misspelled keyword), the formatter will produce output but the query remains invalid. Use a SQL linter or validator for error detection.

What SQL dialects are supported?

Standard SQL, MySQL, MariaDB, PostgreSQL, T-SQL (SQL Server), Oracle PL/SQL, IBM DB2, Amazon Redshift, Spark SQL, Apache Hive, and Couchbase N1QL. Select your dialect from the dropdown for best results.

Is my SQL sent to a server?

No. All formatting runs entirely in your browser using JavaScript. No data leaves your machine. Nothing is stored, logged, or tracked.

What is SQL minification?

Minification removes extra whitespace and line breaks to produce the most compact version of your query. Useful for embedding SQL in code strings, log entries, or configuration files where readability is not the priority.

How do I format a stored procedure?

Paste the full stored procedure including CREATE PROCEDURE and BEGIN/END blocks. Select the correct dialect (T-SQL for SQL Server, PL/SQL for Oracle) for best results with procedural syntax.

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SQL Formatter FAQ