JavaScript, from JSON.parse()
The parser read one complete JSON value and then found more text after it. JSON.parse accepts exactly one value, so a second object, a log line or even a stray character after the closing brace is an error.
Three JSON values on three lines. Press Repair to wrap them into one array.
a {"id": 1, "event": "signup", "user": "ada"}
{"id": 2, "event": "login", "user": "ada"}
{"id": 3, "event": "purchase", "user": "ada", "total": 89.99}
Logs, exports and streaming APIs often use JSON Lines, also called NDJSON, where each line is its own JSON value. Parse it line by line, or press Repair to wrap the lines into one array.
const records = text
.split('\n')
.filter((line) => line.trim())
.map((line) => JSON.parse(line))Appending to a file instead of rewriting it, or a server that writes two responses into one body, leaves two objects back to back. Decide which one you want, or collect them in an array.
An extra } from a bad edit, a trailing semicolon copied from code or a debug message printed to the same output all show up as text after the JSON. The position in the error points straight at it.
A JSON file holds exactly one value, often an array. A JSON Lines file holds one complete JSON value per line, which makes it easy to append to and stream, but it has to be parsed one line at a time.
No, spaces, tabs and newlines after the value are allowed. Only visible characters trigger it, which is what non-whitespace means.