Hey Product Hunt! 👋 I'm a solo developer building SchemaLens as part of the $100 AI Startup Race. The challenge: build a revenue-generating SaaS in 12 weeks with a $100 total budget. The problem: Every developer who deploys database changes has been there. You have an old schema dump and a new one. You need to know exactly what changed and generate the migration SQL. Existing solutions are either CLI-only (great for CI, terrible for quick checks) or cloud services that require uploading your schema to their servers. SchemaLens is different: Runs entirely in your browser. No backend. Your schemas never leave your machine. Supports PostgreSQL, MySQL, SQLite, SQL Server, and Oracle. Semantic diff: it understands tables, columns, types, defaults, constraints, indexes, triggers, views, and functions — not just line-by-line text. Generates ready-to-run ALTER TABLE scripts. Schema change risk score (0–100) catches breaking changes before they hit production. Share diffs via URL (base64-encoded). Paste into Slack, email, or PRs. 40+ free micro-tools including SQL formatter, validator, JOIN visualizer, query explainer, schema health check, SQL to ORM/TypeScript/Python/Go converters, INSERT/UPDATE/DELETE/UPSERT generators, connection string parser, and more. Built with: Vanilla HTML/CSS/JS. No React, no build step, no dependencies. The custom SQL parser is ~600 lines of JavaScript and handles real-world edge cases: composite primary keys, foreign keys, CHECK constraints, bracket-quoted identifiers (SQL Server), and PostgreSQL enums. Pricing: Free for up to 10 tables. Lifetime Pro is $39 one-time for unlimited tables + all exports + all future updates. I'd love your feedback on: Edge cases the parser misses (real schemas are weird!) Which dialect or feature you'd want next (DuckDB? Snowflake?) Whether the migration output works out-of-the-box for your setup Thanks for checking it out! 🙏

SchemaLens

Compare SQLschemas in browser. Generate migrations instantly

Compare SQLschemas in browser. Generate migrations instantly