Ambiguous definitions fail
Duplicate keys, redefined tables, inline-table extension, table-versus-array conflicts, malformed strings, and invalid number or date-time forms fail instead of overwriting earlier values.
- Input
- TOML
- Limit
- 1 MiB
- Runtime
- Browser
Validate TOML syntax and table definitions
Parse TOML strictly and report safe diagnostics and structural facts without formatting or applying an application manifest contract.
Local processingNo sign-upNo content logging
Validate TOML
Inputs are limited to 1 MiB and stay in this browser tab.
Validation report
Nothing is placed in a URL, account, or remote log.
What this tool does
Strict, bounded, local processing
TOML validity proves that a document maps unambiguously to its data model. It does not prove that Cargo, a Python backend, or another consumer accepts its fields.
Consumer rules are separate
Choose the Cargo or pyproject preflight for manifest rules, or supply a bounded schema for a product contract. Syntax validation stops at TOML.
Primary references
Questions and answers
Related TOML tools
TOML FormatterParse valid TOML and write a normalized representation while keeping the complete operation inside the active browser tab.Cargo.toml ValidatorLayer documented Cargo manifest rules over TOML syntax and separate definite errors from checks requiring a workspace, filesystem, registry, or compiler.pyproject.toml ValidatorApply current PyPA metadata rules after TOML parsing and distinguish field errors from filesystem, backend, tool, and index checks.