1. Capture the raw request or response
Start by copying the exact JSON payload from your API client, devtools, or logs. Avoid editing it immediately. You want the real data first, not a cleaned-up version that could hide the original bug.
2. Validate before assuming the API is wrong
If the payload is malformed, the application error may only be a symptom. Use JSON Validator to confirm whether the body is valid JSON at all.
3. Format the payload so the structure is obvious
Nested JSON becomes much easier to inspect after formatting:
{"user":{"id":42,"settings":{"theme":"dark","flags":["beta","admin"]}}}
Readable version:
{
"user": {
"id": 42,
"settings": {
"theme": "dark",
"flags": [
"beta",
"admin"
]
}
}
}
4. Compare expected versus actual fields
Check for missing properties, wrong data types, null values, or extra nesting levels. Those issues are easier to see once the JSON is formatted and the array structure is visible.
5. Watch for escaped string issues
APIs often break when a request body contains text with quotes or line breaks that was escaped incorrectly. The JSON Escape Tool helps when the bug is inside a string field rather than the overall payload shape.
6. Convert or type the payload if needed
After the bug is understood, you may want to turn the sample into TypeScript definitions or flatten it into CSV for investigation. That is where JSON to TypeScript and JSON to CSV fit into the workflow.