TOML Validator
About TOML Validator
The TOML Syntax Validator and Linter verifies TOML documents against the TOML v1.0.0 specification, identifying duplicate keys, type mismatches, invalid datetime formats, and unclosed tables with precise error line indicators.
How to Use TOML Validator
Step 1
Paste your TOML code into the editor.
Step 2
Inspect the validation status badge (VALID / INVALID).
Step 3
Review any reported syntax error alerts.
Step 4
Click "Copy TOML" once validated.
Practical Use Cases for TOML Validator
Rust Cargo.toml & Python pyproject.toml Linting
Validate package manifests and dependency version specs before publishing crates or Python packages.
Cloudflare Wrangler & Netlify Config Validation
Verify `wrangler.toml` and `netlify.toml` build configurations before triggering CI/CD deployment runs.
Input & Output Examples
Catching Duplicate Key in TOML
[server]\nhost = "127.0.0.1"\nhost = "0.0.0.0" (Duplicate key)
TOML Validation Failed: Duplicate key "host" defined at Line 3, Column 1.
Key Features & Performance
- ✓Full compliance with the official TOML v1.0.0 specification.
- ✓Validates strings, integers, floats, booleans, RFC 3339 datetimes, arrays, and tables.
- ✓Reports precise line and column numbers for syntax errors.
- ✓100% Client-Side memory execution guarantees data privacy.
- ✓1-Click Copy validated TOML.
Key Terminology & Definitions
TOML v1.0.0 Specification
The official stabilized standard specification for TOML defining strict syntax rules for keys, data types, and tables.
RFC 3339 Datetime
The ISO 8601 date and time profile required in TOML values (e.g. `1979-05-27T07:32:00Z`).