Has a developer ever asked you to "send it as JSON instead of Excel"? As you use no-code tools, chatbot builders and website admin tools, you meet JSON more and more. Here is a simple explanation of what JSON is and how it maps to Excel.
What is JSON?
JSON (JavaScript Object Notation) is an agreed way of writing data as text. People can read it and programs can parse it easily, so it is the de facto standard for exchanging data between web services.
Three basic building blocks
- Object { }: a set of "name": value pairs. Example: {"name": "Minjun Kim", "team": "Development"}
- Array [ ]: a list of values. Example: ["Development", "Design"]
- Value: a string ("text"), a number (5200), true or false, or nothing (null)
How does an Excel table become JSON?
Take this Excel table:
| name | team | salary |
|---|---|---|
| Minjun Kim | Development | 5200 |
| Seoyeon Lee | Design | 4800 |
Style 1. Array of objects (first row as keys)
The titles in the first row become keys, and each row becomes an object. This is the most common style.
[
{ "name": "Minjun Kim", "team": "Development", "salary": 5200 },
{ "name": "Seoyeon Lee", "team": "Design", "salary": 4800 }
]
Style 2. Two-dimensional array
Rows are copied as arrays. Key names are not repeated, so the result is smaller.
[
["name", "team", "salary"],
["Minjun Kim", "Development", 5200],
["Seoyeon Lee", "Design", 4800]
]
Clean up the sheet before converting
- Only titles in the first row: a report title or an empty row above the titles produces strange keys. Make the table start at cell A1.
- Unmerge cells: merged cells keep the value only in the first cell and leave the others empty.
- Short, unique titles: repeated titles get suffixes like _1. For development, English titles such as name and team are easier to use in code.
- Dates as text: Excel dates are serial numbers internally, so they appear in JSON as numbers like 45678. If you need date strings, format the column as Text and enter values like 2026-10-09.
Try a conversion
- Drop the file into the Excel to JSON converter.
- Choose the sheet and the "Use first row as keys" option.
- Copy the result or download it as a .json file.
The conversion happens in your browser, so internal data such as customer lists and price sheets never passes through an external server.
Checking the JSON result
- Make sure the result starts with "[" and ends with "]".
- If a value that should be a string came out as a number (a postal code, for example), format that column as Text in Excel and convert again.
- Compare the keys with what the receiving system expects, including capitalization and spaces.
Excel and JSON are just two ways of writing the same data. Once you understand the structure, working with developers becomes much easier.