Duplicate keys
What this is
The spec says names should be unique. JSON.parse in JavaScript keeps the last value for a repeated key and does not warn. One parser sees role=user, another sees admin — that is a classic JSON security footgun. This formatter scans the text (not the parsed object) and lists duplicates with a path. Treat them as invalid in APIs you control.
Open the formatter — paste stays in this tab.
{
"role": "user",
"role": "admin"
}FAQ
- Does Repair merge them?
- No. Repair does not delete keys. You decide which value stays.