Validate TOML

Check TOML syntax, table rules, strings, numbers, and dates.

freeworks offlinenothing uploaded
ToolTOML Validator
Input
Output
—
Put this on your own site

The frame below runs the same code as this page, in the reader's own browser. Nothing is sent to us, and nothing is sent to you.

Pick a dark background and the text and panels follow it, so the frame stays readable on a dark page.

Preview

How it works

The TOML parser reads keys, tables, arrays, strings, numbers, booleans, and dates and returns a syntax error when grammar or table rules fail. It does not apply a project-specific schema.

  • Syntax-only validation remains portable across applications.
  • A parser handles multiline strings and quoted keys safely.

Worked example

Valid Cargo.toml
Validate a well-formed Cargo.toml. Returns valid: true
Input
											[package]
name = "my-app"
version = "1.0.0"
Output
												Valid: yes

When to use this

Cargo and Poetry manifests, deployment config, and formatter output use TOML checks.

Edge cases

  • Duplicate table definitions fail even with different keys.
  • Literal strings do not process backslash escapes like basic strings.
  • An unclosed multiline string returns a parser error.

References