Query Studio

Select MySQL as the “From” dialect and PostgreSQL as the “To” dialect, paste your query, and press Translate. Query Studio rewrites the parts that differ between the two databases — backtick identifiers become double quotes, IFNULL becomes COALESCE, and MySQL’s LIMIT/OFFSET is kept in PostgreSQL form — then reformats the result. It’s free, instant, and nothing is stored.

Set PostgreSQL as “From” and MySQL as “To”, then Translate. Double-quoted identifiers become backticks, ANSI functions map to their MySQL equivalents, and standard OFFSET … FETCH row limiting becomes LIMIT. Press the Swap (⇄) button to flip the direction instantly and translate back.

Yes. Choose SQL Server as “From” and PostgreSQL or MySQL as “To”. Query Studio converts bracketed [identifiers], turns TOP n into LIMIT n, maps ISNULL and GETDATE() to COALESCE and the target’s current-timestamp function, and rewrites OFFSET/FETCH paging to the target’s style. The same works in reverse to move from Postgres/MySQL to SQL Server.

Yes, and with no AI. Pick a SQL dialect as “From”, MongoDB as “To”, paste a SELECT and Translate. Query Studio turns it into a MongoDB find() query or an aggregation pipeline — WHERE becomes a filter, JOIN becomes $lookup, GROUP BY becomes $group, and ORDER BY/LIMIT become $sort/$limit — computed deterministically so you get the same result every time.

Translate a query into SQL Server and LIMIT n becomes TOP n inside the SELECT; translate into IBM DB2 and it becomes FETCH FIRST n ROWS ONLY. Query Studio handles both directions automatically and rewrites any OFFSET into the correct pagination syntax for the target database.

Query Studio supports 18 dialects. On the SQL side: MySQL, PostgreSQL, SQLite, MariaDB, SQL Server, IBM DB2, Snowflake, Amazon Redshift, Google BigQuery, DuckDB, Spark SQL, Hive, Trino and Presto. It also converts SQL to MongoDB, and formats and validates GraphQL, Elasticsearch and OpenSearch. Everything is free with no account.

It’s completely free with no account and no usage limits. Translate, Explain, Visualize, Analyze, Optimize, Format, Validate and the ER Diagram tool all run for free — nothing is trial-limited or paywalled, and there’s nothing to install.

No. Your query is processed on the server only to return the result, then discarded — it is never saved, logged against you, or shared, and there is no sign-in. As good general practice, avoid pasting real credentials or secrets into any online tool.

No. Every result is computed deterministically by real SQL parsers and rule engines — so it’s instant, free, unlimited, and gives the same answer every time. Nothing is sent to an AI service, which also means no rate limits and no surprises in the output.

SQL is written SELECT-first, but a database executes it FROM-first: FROM and JOIN, then WHERE, then GROUP BY, HAVING, SELECT, window functions, ORDER BY, and finally LIMIT. The Explain and Visualize tabs walk your query through this real order — which is why, for example, you can’t use a SELECT alias inside WHERE.

WHERE filters individual rows before grouping and cannot see aggregates; HAVING filters whole groups after GROUP BY and can test aggregates like COUNT(*) > 3. Run Explain on a grouped query to see exactly where each clause runs in the execution order.

It statically scans for well-known anti-patterns — SELECT *, UPDATE or DELETE without WHERE, cartesian joins, leading-wildcard LIKE, functions applied to filtered columns, unbounded ORDER BY and more — and subtracts points by severity to produce a 0–100 score and letter grade, with an explanation for every finding.

The Optimizer gives concrete rewrites — turning IN (SELECT …) into a JOIN or EXISTS, collapsing OR into IN, removing needless DISTINCT — plus CREATE INDEX candidates from your WHERE and JOIN columns. It also flags non-sargable predicates: filters the database can’t use an index for, usually because a column is wrapped in a function (WHERE YEAR(created_at) = 2024) or a LIKE pattern starts with a wildcard.

Open the Diagram tab, paste one or more CREATE TABLE statements, and press Diagram. Query Studio parses your tables, primary keys and foreign keys and draws an entity-relationship diagram with connectors between related columns — no login and nothing to install.

Yes. Pick GraphQL, Elasticsearch DSL or OpenSearch as the dialect and use the Format or Validate tab. GraphQL is parsed and pretty-printed with the official GraphQL parser; Elasticsearch and OpenSearch request bodies are validated and beautified as JSON.

Yes. After any result, a “Use this result →” bar sends the output straight into another tool — translate a query, then Explain, Analyze or Optimize the translated version in one click, with no copy-pasting.