TOON vs CSV: Tabular Data Formats

Both TOON and CSV excel at representing tabular data. Discover how TOON adds structure to CSV's simplicity.

Format Comparison

CSV Example

id,name,role,salary
1,Alice,Engineer,120000
2,Bob,Designer,95000
3,Charlie,Manager,135000

Simple, compact, but no metadata or nesting

TOON Example

employees[3]{id,name,role,salary}:
  1,Alice,Engineer,120000
  2,Bob,Designer,95000
  3,Charlie,Manager,135000

Similar size but with explicit structure and count

Key Advantages

CSV Strengths:

✓ Maximum simplicity
✓ Smallest file size
✓ Universal support (Excel, databases)
✓ Easy to generate/parse
✓ Standard format (RFC 4180)

TOON Advantages:

✓ Explicit structure (array length, field names)
✓ Supports nested objects
✓ Mixed data types in same document
✓ Better LLM parsing (explicit schema)
✓ Self-documenting format

Handling Complex Data

CSV Limitation

CSV cannot represent nested structures without flattening or using multiple files:

# user.csv
id,name,department
1,Alice,Engineering

# addresses.csv (separate file)
user_id,street,city,zip
1,123 Main St,Boston,02101
1,456 Oak Ave,Cambridge,02139

Requires joins and multiple files for relational data

TOON Solution

TOON naturally handles nested data in a single document:

user:
  id: 1
  name: Alice
  department: Engineering
  addresses[2]{street,city,zip}:
    123 Main St,Boston,02101
    456 Oak Ave,Cambridge,02139

Single file with clear structure and relationships

LLM Parsing Accuracy

Why TOON Parses Better Than CSV for AI:

Explicit Schema: TOON declares field names and count upfront, reducing ambiguity

Type Clarity: Context makes data types obvious (CSV "true" could be string or boolean)

Mixed Content: Can combine tables with objects/metadata in same document

Header Redundancy: No need to reference header row - schema is inline

Real-World Example: Product Catalog

CSV Format(Multiple files required)

# products.csv
product_id,name,price,category
101,Laptop,999,Electronics
102,Mouse,29,Electronics
103,Desk,299,Furniture

# inventory.csv (separate file)
product_id,warehouse,quantity
101,Boston,45
101,Seattle,23
102,Boston,120
102,Seattle,89
103,Boston,12

TOON Format(Single file, better structure)

products[3]{product_id,name,price,category}:
  101,Laptop,999,Electronics
  102,Mouse,29,Electronics
  103,Desk,299,Furniture

inventory[5]{product_id,warehouse,quantity}:
  101,Boston,45
  101,Seattle,23
  102,Boston,120
  102,Seattle,89
  103,Boston,12

Token Efficiency vs File Size

Metric	CSV	TOON	Winner
File Size (bytes)	Smaller	Slightly larger	CSV
Token Count (LLM)	Similar	Similar*	Tie
Parsing Accuracy	Good	Excellent	TOON
Nested Data Support	No	Yes	TOON
Self-Documenting	Partial	Yes	TOON
Tool Compatibility	Universal	Growing	CSV

* TOON adds minimal overhead (array count + field names) but gains significant structure benefits

When to Use Each Format

Use CSV For:

Spreadsheet imports/exports
Database dumps
Pure tabular data with no nesting
Maximum compatibility with tools
Smallest possible file size

Use TOON For:

LLM prompts with tabular data
Mixed structured and nested data
Self-describing datasets
AI applications needing explicit structure
Documents with multiple data types

The Bottom Line

TOON builds on CSV's tabular efficiency while adding structure and support for nested data. For pure tabular data exports to spreadsheets or databases, CSV is simpler and more compatible. For LLM applications needing both tabular efficiency, explicit structure, and the ability to mix data types, TOON is the superior choice. TOON essentially gives you "CSV with context."

Convert to TOON Format

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