SQL Formatter — Format & Beautify SQL Queries Online

SQL Formatter is a free, privacy-first tool that turns messy SQL queries into clean, readable code in milliseconds. Configure indent size, keyword casing, and comma style — all processing runs entirely in your browser, so your queries never leave your device.

The Problem with Raw SQL

SQL queries get messy fast. An ORM dumps a minified join across five tables. A legacy stored procedure has inconsistent indentation and lowercase keywords mixed with uppercase. You're debugging a production incident and you need to read the query — now.

Reformatting by hand is slow. Pasting into a text editor helps but doesn't understand SQL structure. Most online formatters send your query to a server, which is a risk when it contains schema details, credentials, or proprietary business logic.

How SQL Formatter Works

1. Tokenizer-Based Formatting

SQL Formatter uses a custom tokenizer that splits the query into typed tokens: keywords, identifiers, strings, operators, and comments. It understands SQL structure rather than just applying whitespace rules, so it:

• Places each major clause (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY) on its own line
• Indents AND/OR conditions under the clause they belong to
• Handles subqueries with nested indentation
• Preserves string literals and quoted identifiers exactly as entered
• Formats CASE expressions with WHEN/THEN/ELSE on separate lines

2. Configurable Output

Every team has a SQL style preference. SQL Formatter lets you set:

• Indent size: 2 spaces (compact) or 4 spaces (spacious)
• Keyword casing: UPPERCASE (most common convention) or lowercase
• Comma style: trailing comma (standard) or leading comma (dbt-style)

3. Minify Mode

Collapse formatted SQL into the smallest valid form — useful for embedding queries in application strings, comparing two queries character-by-character, or reducing log verbosity. Minify removes all extra whitespace, newlines, and SQL comments.

4. Download as .sql

Export the formatted or minified output as a .sql file for version control, documentation, or sharing with teammates.

Key Features

• Instant formatting — tokenizer runs in milliseconds with no server roundtrip
• Format + Minify tabs — switch between beautify and minify modes
• Configurable indent — 2 or 4 spaces
• Keyword casing — UPPERCASE or lowercase
• Comma style — trailing or leading (dbt-style)
• Copy to clipboard — one-click copy
• Download as .sql — export formatted output
• 100% client-side — your SQL never leaves your browser
• Minification stats — shows byte savings when minifying

Dialect Support

SQL Formatter understands keywords from the three most common open-source databases:

• MySQL — REPLACE INTO, ON DUPLICATE KEY UPDATE, backtick-quoted identifiers
• PostgreSQL — RETURNING, ILIKE, ON CONFLICT, dollar-quoted strings, :: cast syntax
• SQLite — core SQL with minimal extension keywords

Technical Implementation

Stack

• Next.js 16 with App Router
• TypeScript (strict mode) — all formatter logic is typed
• Custom SQL tokenizer — no external formatter library dependency
• shadcn/ui + Tailwind CSS v4 for styling
• Framer Motion for UI animations
• Sonner for toast notifications

Architecture

The formatter is implemented in three layers:

1. Tokenizer — character-by-character scanner that produces a stream of typed tokens (KEYWORD, IDENTIFIER, STRING, NUMBER, OPERATOR, etc.)
2. Formatter — a single-pass token consumer that maintains indent state, paren stack, and clause context
3. Minifier — a regex-based pass that removes comments and collapses whitespace

No external SQL parsing library is used. The formatter is deliberately simple and predictable — it formats 95% of real-world SQL queries correctly without the complexity of a full AST parser.

Use Cases

Debugging API Queries

Copy a raw SQL query from your ORM logs or database slow-query log and paste it in. See the full join structure, filter conditions, and subqueries in a readable format — without leaving your browser.

Code Reviews

Formatters bring consistency. Reviewing a PR that includes SQL? Format both versions and compare. Consistent keyword casing and indentation make structural changes obvious and noise minimal.

Documentation

Clean SQL is easier to document. Format your key queries before including them in README files, architecture docs, or internal wikis.

Learning SQL

Reading formatted SQL is easier than reading a wall of text. Students and developers learning SQL structure can paste any query and immediately see how clauses relate.

Embedding in Code

Minify SQL before embedding it in application code strings or config files. The minified output is still valid SQL and significantly smaller.

Why Not Just Use a Text Editor?

Text editors reformat syntactically — they indent based on brackets and whitespace rules. SQL Formatter formats semantically — it understands that WHERE starts a clause, that AND belongs to a condition, and that (SELECT ...) is a subquery requiring deeper indentation.

A text editor doesn't know the difference between a comma in a function call and a comma separating SELECT columns. SQL Formatter does.

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Try it now: sql-formatter.tools.jagodana.com