• Multi-table workspaces — up to 10 tables in one workspace
• Table renaming — give a table a cleaner name than its raw filename
• Cross-table AI queries — the assistant writes joins across your tables
• More AI usage — 5x the daily limit on a free account
• Relationship detection — auto-suggested foreign keys you confirm yourself
• Large files — load CSVs up to 500,000 rows instead of 50,000

✓ $9.99, paid once. Not a subscription, so there's nothing to cancel later.

✓ Early-adopter price — $9.99 while Synth is in beta.

✓ 7-day guarantee. Not what you expected? Email us, no questions asked.

Upload a CSV and it loads into a real SQLite database running entirely in this browser tab. Nothing is sent to a server unless you sign in and choose to save it.

Each CSV loads into a table named after its file (click the pencil on a table chip to rename it). Write queries as SELECT * FROM table_name .... The chip bar above the tabs always shows the current names.

+ Add table builds a multi-table workspace (up to 10 tables) that the AI can join across. Open the Relationships tab to see auto-suggested foreign keys, shown dashed and grey and matched by column name. Confirm the real ones, or drag between two columns to connect them manually and pick a cardinality (1:1, 1:M, M:M, etc.). Only confirmed relationships, shown solid blue, are shared with the AI as join hints.

Table View always shows the full contents of whichever table is selected in the chip bar. Query Results only shows the output of the last query you ran. Both get a Download CSV button once there's data on screen, and it exports exactly what's visible, including any active filter, search, or sort.

Upload CSV starts a brand-new workspace and replaces everything currently loaded. + Add table adds more files to the workspace you already have open instead. Save anything important first if you're signed in.

Switch modes anytime with the SQL / General toggle above the chat. SQL Mode only ever replies with a runnable query. Click Use Query to drop it into the editor, then hit Run. General Mode answers in plain English instead, with no query generated, so there's no Use Query button, just the copy icon. Either way, an off-topic question gets a plain answer instead of a made-up query. With more than one table loaded, use the AI focus dropdown to hint which table(s) an ambiguous question should default to. A question that clearly needs a join still works regardless of focus. Click ↩ Reply under any answer to ask a follow-up with that answer quoted as context.

Save Query and Load Query keep a personal list of queries for the current file, stored in this browser. They don't sync across devices. Saving a query requires a free account — Lite Mode can fill out the Save Query form, but signs you in before it actually saves.

If you're signed in on Normal Mode, Save to cloud and Save session (in the AI panel) store the current workspace and chat history to your account. Open Load Sessions, top right, to reopen anything you've saved, from any device. Lite Mode never touches the cloud, so nothing here happens unless you sign in and click Save.

• Multi-table workspaces: up to 10 tables in one workspace instead of one
• Table renaming: give a table a cleaner name than its raw filename
• Cross-table AI queries: the assistant writes joins across your tables
• More AI usage: 5x the daily limit on a free account
• Relationship detection: auto-suggested foreign keys you can confirm in the Relationships tab
• Large files: load CSVs up to 500,000 rows instead of 50,000

✓ $9.99, paid once. Not a subscription, so there's nothing to cancel later. Early-adopter price while Synth is in beta, backed by a 7-day guarantee.