Learn JSON
Short guides in plain English. Each one ends with a thing you can try in the tool.
What is JSON? A complete guide
The whole JSON format in one page: the six kinds of value, the rules, the traps, and what JSON cannot do.
The 12 most common JSON errors, and how to fix each one
Every JSON error message you are likely to meet, what it really means, and the fix.
Can JSON have comments? JSON, JSONC and JSON5
Why the JSON standard has no comments, what people do instead, and how JSONC and JSON5 differ.
JSONPath in five minutes
Find anything in a JSON document with a short expression. Every operator, with examples you can run.
How to open a large JSON file without a freeze
Why most viewers die at 20 MB, what to do instead, and how to read a file of several hundred megabytes.
JSON Lines (NDJSON): what it is and when to use it
One JSON value a line. Why logs and data exports use it, and how to read, write and convert it.
How to compare two JSON files
Why a plain text diff fails on JSON, what a real JSON comparison does, and how to read the result.
How to turn JSON into CSV
The rules for flattening nested data into columns, the traps, and three ways to do it.
How to turn JSON into a TypeScript interface
Get types from a real API answer in seconds, and know what the generated types cannot tell you.
JSON Schema — check your data before it breaks something
Write a schema that catches bad data, with the keywords that matter and the traps that waste a day.
Why big numbers break in JSON, and what to do
An identifier of 19 digits goes into a parser and comes out changed. Here is why, and the three ways to stop it.
Is it safe to paste JSON into an online viewer?
What really happens to your data in a web tool, how to tell an upload from local work, and when to say no.