TOML Validator & Formatter

A powerful tool for validating and formatting TOML configuration files. Perfect for Cargo.toml, pyproject.toml, and other TOML-based configurations.

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Input

# This is a complex TOML document that tests various edge cases
# Including unicode: コメント

title = "Complex TOML Example ✨"
description = """
Multi-line strings
can contain "quotes"
and 'single quotes'
and even Unicode: 🌟
"""
empty_string = ""
basic-string = "I'm a string. \"You can quote me\". Name\tJos\u00E9\nLocation\tSF."

# Different number formats
int1 = +99
int2 = 42
int3 = 0
int4 = -17
int5 = 1_000
int6 = 5_349_221
int7 = 1_2_3_4_5     # valid but unusual
hex1 = 0xDEADBEEF
hex2 = 0xdeadbeef
hex3 = 0xdead_beef
oct1 = 0o01234567
oct2 = 0o755
bin1 = 0b11010110

# Fractional numbers
flt1 = +1.0
flt2 = 3.1415
flt3 = -0.01
flt4 = 5e+22
flt5 = 1e06
flt6 = -2E-2
flt7 = 6.626e-34
flt8 = 224_617.445_991_228
inf = inf  # infinity
nan = nan  # not a number

# Booleans
bool1 = true
bool2 = false

# Dates and times in different formats
odt1 = 1979-05-27T07:32:00Z
odt2 = 1979-05-27T00:32:00-07:00
odt3 = 1979-05-27T00:32:00.999999-07:00
odt4 = 1979-05-27 07:32:00Z
date1 = 1979-05-27
time1 = "07:32:00"
time2 = "00:32:00.999999"

# Array examples
integers = [ 1, 2, 3 ]
colors = [ "red", "yellow", "green" ]
nested_arrays_of_ints = [ [ 1, 2 ], [3, 4, 5] ]
nested_mixed_array = [ [ 1, 2 ], ["a", "b", "c"] ]
string_array = [ "all", 'strings', """are the same""", '''type''' ]

# Mixed-type arrays
numbers = [ 0.1, 0.2, 0.5, 1.0, 2.0, 5.0 ]  # All must be floats
# Array of tables is more appropriate for structured contributor data
[[contributors]]
name = "Foo Bar"
email = "foo@example.com"

[[contributors]]
name = "Baz Qux"
email = "bazqux@example.com"
url = "https://example.com/bazqux"

# Array of tables
[[fruits]]
name = "apple"
[fruits.physical]  # nested table
color = "red"
shape = "round"
[fruits.variety]
name = "red delicious"

[[fruits]]  # Array of tables
name = "banana"
[[fruits.varieties]]  # nested array of tables
name = "plantain"
[[fruits.varieties]]
name = "yellow"
details = { color = "yellow", shape = "curved" }  # inline table

# Deeply nested structures
[deeply.nested.structure]
prop1 = "value1"
prop2 = "value2"
[deeply.nested.structure.more]
prop3 = "value3"
[[deeply.nested.structure.more.items]]
name = "item1"
[[deeply.nested.structure.more.items]]
name = "item2"

# Edge cases for tables and arrays
[empty-table]

[with-empty-array]
empty = []

[with-empty-inline-table]
empty = {}

# Quoted keys and special characters
"127.0.0.1" = "value"
"character encoding" = "UTF-8"
'key2' = "value"
'quoted "value"' = "value"

# Different table formats
[simple]
key = "value"

[data."~!@$^&*()_+-=[]|;:,.<>?"]
special = true

# Challenging string escapes
escaped-strings = [
    "Here's a quote \"",
    "Here's a quote \"",
    """
Multiple
lines \u0000 with
unicode \U0000F000
and escapes \t\n\r
""",
    '''
Also multiple
lines with
'single' "double"
quotes
'''
]

# Real-world application simulation
[servers]
alpha.ip = "10.0.0.1"
alpha.hostname = "alpha"
alpha.enabled = true
beta.ip = "10.0.0.2"
beta.hostname = "beta"
beta.enabled = false

[dependencies]
substrate = { version = "3.0", default-features = false, features = ["std", "runtime-benchmarks"] }
tokio = { workspace = true, features = ["full"] }
serde = { version = "1.0", features = ["derive"] }

Validation Result

✓ TOML is valid

About This Tool

This enhanced TOML validator and formatter supports the full TOML 1.0 specification and provides extensive formatting options. Perfect for working with various TOML-based configuration files.

Common Uses:

Cargo.toml (Rust package manager)
pyproject.toml (Python project configuration)
Poetry dependency files
Application configuration files
Build system configurations

Key Features:

Full TOML 1.0 specification support
Schema validation for common TOML file types
Customizable array and table formatting
DateTime format standardization
File upload and download capabilities
Comment preservation
Section and key sorting options
Line-specific error highlighting

Schema Presets:

cargo: Basic Cargo.toml validation

pyproject: Basic pyproject.toml validation

Format Presets:

standard: Standard TOML format with good readability

compact: Minimized format for storage efficiency

cargo: Rust Cargo.toml style formatting

pyproject: Python pyproject.toml style formatting

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