Free SQL & Database Tools Online
Free online SQL and database tools: format SQL, run SQLite queries, visualize MySQL/MariaDB execution plans, convert CSV or JSON to SQL, generate IN clauses, convert SQL DDL to application types, and troubleshoot database errors.
Core Online Tools
Full-featured, standalone web applications for day-to-day SQL workflows.
CSV to SQL Converter
Convert CSV, TSV, or spreadsheet exports into relational table schemas and batched INSERT statements. Automatically infers data types and formats dates and numbers.
- Auto delimiter & type inference
- 100–1,000 row batch chunking
- Direct handoff to SQLite Playground
JSON to SQL Converter
Convert JSON arrays, NDJSON/JSON Lines, or API objects into SQL tables and batch INSERT statements. Flattens nested keys or preserves native JSON/JSONB.
- Auto type detection & JSON schema inference
- Flatten nested objects or keep JSONB
- Direct handoff to SQLite Playground
SQL IN Clause Generator
Format lists from Excel, CSV, or logs into SQL IN clauses. Deduplicates items, quotes strings safely with SQL escape, and chunks queries to bypass Oracle 1,000 limits.
- Automatic duplicate removal & counter
- Chunk by 1,000 for Oracle (ORA-01795)
- Compact, multi-line, or parameterized (?, ?)
SQL Formatter
Format, align, and standardize raw SQL queries into clean, readable code. Customize indentation, keyword casing, and dialect syntax rules instantly.
- Uppercase / Lowercase / Preserve case
- 2-space or 4-space custom indentation
- Keyboard shortcut: ⌘+Enter / Ctrl+Enter
SQLite SQL Playground
Execute SQL statements in an in-memory SQLite database powered by official WebAssembly. Open and inspect local .db files up to 25 MiB with zero server upload.
- Live query runner with tabular results
- Import and export local .sqlite/.db files
- Preloaded demo schema (Employees, JSONB)
SQL to Types & Models Converter
Convert SQL CREATE TABLE statements into TypeScript interfaces, Python Pydantic models, Go structs, Rust structs, and JSON Schema. Infers types, nullability, and primary keys.
- Multi-dialect DDL (Postgres, MySQL, SQLite, T-SQL)
- Nullable, optional, and camelCase mapping
- Direct handoff to SQLite Playground & Formatter
MySQL & MariaDB EXPLAIN Plan Visualizer
Inspect JSON execution plans locally. Visualizes table access methods, selected keys, candidate indexes, estimated rows, and runtime metrics without connecting to a database.
- Auto highlights full table scans (`ALL`)
- Estimates vs actual runtime (`r_rows`, `r_loops`)
- Extracts JSON from CLI output with borders
Database Diagnostic & Troubleshooting Helpers
Lightweight in-browser calculators, schema validators, and triage assistants embedded in our database guides.
Error Lookup & Triage
Quickly filter error catalogs and triage database authentication failures.
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MySQL Error Code Filter MySQL
Instant search across official MySQL error codes and messages.
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PostgreSQL SQLSTATE Filter Postgres
Search the PostgreSQL catalog by 5-character SQLSTATE code.
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PostgreSQL Error Triage Helper Postgres
Interactive wizard to diagnose syntax and transaction errors.
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MySQL Connection & Auth Triage MySQL
Distinguish 1045, 1524, 2059, and network access blocks.
Connection & Pool Calculators
Calculate safe pool allocations to avoid connection exhaustion errors.
Schema & Syntax Checkers
Validate constraints, identifier spelling, and JSON schemas.
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MySQL Foreign Key Checker MySQL
Validate column types, signs, collations, and parent keys.
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MySQL Column Name Checker MySQL
Find close spelling suggestions for Error 1054 mismatches.
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PostgreSQL Column Checker Postgres
Detect case-sensitivity issues in quoted identifiers.
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JSON Schema Validator MariaDB
Validate JSON documents against Draft 2020-12 schemas.
Client-Side Privacy & Security Guarantee
How SQLiz protects your databases, spreadsheets, and query text.
All checks, data conversions, the SQL formatter, and the SQLite playground run exclusively in your browser and do not connect to a database server.
When analytics is enabled, SQLiz records only aggregated, anonymous interaction metadata (e.g. formatter dialect choice, validation success/error outcome, link clicks). SQLiz never collects, inspects, or transmits entered SQL statements, table schemas, connection credentials, uploaded CSV files, database contents, or query result values.