SQL formatter online + JSON CSV converter

Why SQL formatting matters

Unformatted SQL is one of the most common sources of debugging friction in backend development. A 20-line query crammed onto one line with inconsistent casing makes it hard to spot a missing JOIN condition, a wrong GROUP BY column, or a subquery that returns multiple rows where one is expected. Proper formatting surfaces structure — each clause on its own line, indented subqueries, aligned column lists.

Code review is faster when SQL is readable. Reviewers can scan the SELECT list for unexpected columns, verify WHERE conditions cover all necessary filters, and check that JOINs use the right join type without running the query. Formatted SQL also pastes cleanly into documentation, tickets, and analytics dashboards.

SQL dialect differences

Most SQL formatting conventions work across dialects (PostgreSQL, MySQL, SQLite, SQL Server, BigQuery, Snowflake), but dialects differ in details. PostgreSQL uses double quotes for identifiers and single quotes for string literals. MySQL uses backticks for identifiers. SQL Server uses brackets ([column_name]). BigQuery uses backticks like MySQL but supports ANSI double quotes with a flag.

Function names and date handling vary significantly: PostgreSQL has NOW() and CURRENT_TIMESTAMP; MySQL has SYSDATE(); SQL Server has GETDATE(). Window functions (OVER(), PARTITION BY, ROW_NUMBER()) are supported in all modern databases but with slightly different syntax in edge cases. The formatter normalizes keyword casing and spacing but preserves dialect-specific identifiers.

Formatting conventions that improve readability

Uppercase reserved words (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY, HAVING, LIMIT) contrast with lowercase table and column names, making the structure scannable. Each major clause starts on a new line. Columns in SELECT lists, JOIN conditions, and GROUP BY are each on their own line with consistent indentation — especially important for queries with 10+ columns.

CTEs (Common Table Expressions) using WITH ... AS (...) are a major readability win for complex queries. Each CTE gets a meaningful name and is formatted as its own indented block. The final SELECT reads cleanly because the intermediate logic has a named reference. Formatting tools that properly indent CTEs save significant manual effort when working with analytical queries.

Subqueries in WHERE and FROM clauses benefit from indentation that shows nesting depth. A subquery that returns one value (scalar subquery) behaves differently from one used in EXISTS — this distinction is clearer when the subquery is properly indented and isolated. The SQL formatter on this page handles standard formatting automatically, leaving you to focus on query logic rather than presentation.