SQL Formatter and Minifier

Formatting SQL is less about adding line breaks and more about knowing which characters are code and which are content. A regex that finds keywords and inserts newlines will happily break a statement containing WHERE remark LIKE '%; SELECT 1' or -- a comment that also mentions FROM. This tool performs a full lexical pass first, then touches only whitespace between code tokens; strings, comments and identifiers are left byte for byte.

Three modes

• Format: clause breaks and layered indentation, for reading long reporting SQL, writing design docs or pasting into a ticket
• Minify: collapse a statement to one line for logs, config files and scheduler arguments, or to normalize both sides before a diff. Line comments become block comments so they cannot swallow the rest of the line, or can be removed entirely
• Whitespace only: keep your line structure and fix only excess spaces and spacing around operators, the smallest change for a project that is already formatted

Formatting rules

• Top-level clauses on their own lines: SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY, LIMIT, INSERT, UPDATE, SET, VALUES and WITH. Multi-word clauses are recognized as a unit, so GROUP and BY are never split across lines
• AND, OR and XOR on separate lines: with many conditions, aligned rows make the missing parenthesis easy to spot
• Layered JOINs: INNER, LEFT, RIGHT, FULL, CROSS and NATURAL each start a line, and ON or USING conditions indent one level, so multi-table joins no longer form one long horizontal line
• CASE expanded line by line: WHEN, ELSE and END each get a line, and END never swallows the following SELECT list, a common failure in online formatters
• IN lists wrap by threshold: above the threshold, six by default, each element gets a line; below it the list stays as is. Function parentheses, OVER (...) windows and VALUES tuples are never split
• Subqueries and parentheses add a level: the structure of CTEs, EXISTS and derived tables is visible from indentation alone
• Blank lines between statements, with a summary of statement count, result rows, maximum depth and input characters

What the lexer protects

• Strings: single and double quotes, doubled quotes as an escaped quote, backslash escapes, multi-line strings, and prefixed forms such as E'', N'', X'', B'' and U&'' are emitted unchanged
• Identifiers: backtick names with spaces, bracketed names, double-quoted identifiers and non-ASCII column names stay whole and are never cut into a keyword plus fragments
• Comments: -- and # line comments and block comments keep their position. A line comment keeps its newline and is never merged into a code line
• Parameters and placeholders: @@variables, :named parameters and ? placeholders are not treated as operators
• Multi-character operators: >=, <>, !=, ||, ::, ->> and ?. stay single symbols and never split into two that change meaning
• Numbers: scientific notation, leading decimal points and hexadecimal literals each remain one token

Options

FAQ

• Can a semicolon inside a string end the statement? No. Only semicolons outside quotes and comments count as boundaries. The sample SQL includes ';cancelled; note' with semicolons and parentheses specifically to prove this
• What if parentheses or quotes do not balance? The page reports the approximate line and character and stops instead of returning half-broken SQL. A partial result is more dangerous than an error because it looks runnable
• Can the minified statement be executed? Yes. Strings and identifiers are preserved and only whitespace changes. Line comments become block comments or are removed, since -- would otherwise consume the rest of the line
• Which dialect is supported? Mostly common MySQL and PostgreSQL syntax: backticks, brackets, prefixed strings, :: casts, window functions and CTEs. Dollar quoting with $$ and procedural blocks are not implemented, so stored procedures need manual review
• What if a table name matches a keyword? Wrapping it in backticks or double quotes makes it an identifier. A bare name that matches a keyword and is immediately followed by an opening parenthesis is treated as a function call and not as a clause break
• Does a large SQL file stall? Formatting is a single pass and handles hundreds of thousands of characters in seconds. Statement count matters more for readability; the split view lets you inspect and copy each statement
• Is the data uploaded? No. Tokenizing, formatting, highlighting, copying and download all run in page JavaScript with no requests and no server, so offline intranet use works
• How is whitespace only different from format? Format reflows line breaks and indentation. Whitespace only keeps your line positions and just normalizes extra spaces and operator spacing, which suits a team style that only needs stray spaces removed

After formatting, tidy embedded JavaScript with the JS formatter; clean up API JSON with the JSON formatter; batch edit column lists with text replace and line operations; compare two SQL files with the text diff; test validation patterns from DDL with the regex tester.