XML, JSON, TOML, YAML: Which One is the Secret Key to Your Data Success?

4 min readSep 22, 2023

In the grand performance of data, we find compositions that often are taken for granted, one of which are data formats. These unsung heroes are the silent enablers that hold the power to make our data dance to our tunes.

Today, we’ll shine the spotlight on four popular examples:

XML, JSON, TOML, and YAML.

We’ll evaluate these heroes on four key criteria:

Efficiency, Complexity, Readability, and Error Handling.

XML: A Versatile Virtuoso

Extensible Markup Language, is the seasoned conductor, capable of orchestrating complex, hierarchical symphonies of data, at the cost of some simplicity.

<album>
    <title>The Symphony of Sounds</title>
    <artist>The Virtuosos</artist>
    <year>2022</year>
    <tracks>
        <track>
            <title>Overture of Efficiency</title>
            <duration>4:30</duration>
        </track>
        <track>
            <title>Ballad of Simplicity</title>
            <duration>5:20</duration>
        </track>
    </tracks>
</album>

Efficiency: XML’s performance is a bit like a grand opera — rich, elaborate, but not particularly concise. The use of opening and closing tags can lead to a bit of a data bloat.
Complexity: XML can be a tough nut to crack with its nested and self-referential structures.
Readability: XML is self-descriptive, which aids readability, but its verbosity can make it feel like reading a novel rather than a quick note.
Error Handling: XML’s use of closing tags can help in identifying incomplete structures, offering a safety net against data mishaps.

JSON: An Agile Artisan

In full, JavaScript Object Notation, is the nimble craftsman of data formats. Although, its meant to be machine-readable rather than human-readable. However the case, it’s lightweight, agile, and gets the job done efficiently.

{
    "album": {
        "title": "The Symphony of Sounds",
        "artist": "The Virtuosos",
        "year": 2022,
        "tracks": [
            {
                "title": "Overture of Efficiency",
                "duration": "4:30"
            },
            {
                "title": "Ballad of Simplicity",
                "duration": "5:20"
            }
        ]
    }
}

Efficiency: JSON is more efficient than XML, especially for complex nested structures, but it can still be a bit verbose.
Complexity: JSON is as straightforward as a craftsman’s tool — easy to parse and generate. Lending to the popularity its composed over the years.
Readability: JSON’s simplicity and structure make it as easy to understand as a well-crafted blueprint.
Error Handling: JSON’s error handling capabilities are a bit limited. A missing bracket, for example, can cause the whole structure to fall flat.

YAML: A Friendly Harmonizer

YAML Ain’t Markup Language, is the people’s champion in recent time. It’s a human-friendly data format that’s often used for configuration files. While still nested, your eyes can relax in comparison to the previous contenders.

album:
  title: The Symphony of Sounds
  artist: The Virtuosos
  year: 2022
  tracks:
    - title: Overture of Efficiency
      duration: 4:30
    - title: Ballad of Simplicity
      duration: 5:20

Efficiency: YAML makes use of whitespace for nesting; like a well-composed song — it saves space and is pleasing to the eye.
Complexity: YAML can be a bit tricky due to its reliance on indentation and the possibility of multiple documents.
Readability: YAML is designed for human readability, making it as easy to understand as your favorite book.
Error Handling: YAML’s reliance on whitespace can make errors tricky to catch, making it a bit of a wild card in error handling.

TOML: A Minimal Maestro

Tom’s Obvious, Minimal Language is the newest of these data formats. It’s simple, clean, and gets straight to the point. While still being readable, it maintains a solid structure throughout.

[album]
title = "The Symphony of Sounds"
artist = "The Virtuosos"
year = 2022

[[album.tracks]]
title = "Overture of Efficiency"
duration = "4:30"

[[album.tracks]]
title = "Ballad of Simplicity"
duration = "5:20"

Efficiency: TOML is designed to be minimal, making it the epitome of efficiency.
Complexity: While TOML is generally simple, in-line tables and arrays can add a bit of a twist.
Readability: TOML is designed to be human-readable, making it as easy to read as a well-written novel.
Error Handling: TOML’s clear section delineation offers a safety net against data mishaps.

A Final Note

When it comes to efficiencies, TOML and YAML are the virtuosos, offering the most compact representations.

In terms of complexity, JSON is the easy-going artisan, followed by TOML, YAML, and the more complex XML.

Crucial to understanding is the readability of all four formats are present, but TOML, YAML, and yes even JSON are generally easier to reason through due to their simplicity.

When casing for error handling, XML and TOML offer more robustness against malformed data, acting as the safety nets in our data orchestra.

Utlimately, choosing the correct data format is like choosing the correct instrument for a symphony. It depends on the specific needs, including how the data will be used after it’s processed. By understanding these strengths and weaknesses of each format, you can configure a data composition that hits all the right notes.

So, which one is the key to your data? Drop a comment below to keep the conversation going.