Expected ',' or '}' after property value in JSON

The fix

Add the comma at the end of the line above the position, as in the fixed example. If that line already ends in a comma, look for a double quote inside a string just before the position and escape it.

{
  "id": 7,
  "name": "Ada"
  "email": "ada@example.com",
  "active": true
}

{
  "id": 7,
  "name": "Ada",
  "email": "ada@example.com",
  "active": true
}

How the message appears

Chrome and Node first, then Firefox, then Safari. The next three are the same fault in an array. The line after those is Chrome for an unescaped quote inside a string. Node 20 leaves out the line and column. Safari never says a comma is missing.

What causes it

1. 1

   A comma is missing between two members

   The example has no comma after "Ada". The other members have their commas. JSON.parse reads "Ada", then meets the " of "email" on the next line and stops. So the position is that quote, on line 4, and the line you have to edit is the one above it, line 3. Add the comma at the end of that line.

2. 2

   A double quote inside a string

   Take {"quote": "she said "hi" to me"}. The quote before hi ends the string "she said ", so the next character is the h, and Chrome points at it. The mistake is the quote just before the position, not the text at the position. Escape the quote as \".

3. 3

   A missing comma in an array

   In a list the message says after array element and asks for , or ]. [1 2] stops at the 2. Firefox says the same thing in its own words. Safari says only Expected ']'.

4. 4

   The document stops after a value

   Chrome and Node give this message when a body is cut off right after a value, and the position is the end of the text. If the position is the last character, look for a response that was cut short. See Unexpected end of JSON input.

5. 5

   Safari says only Expected '}'

   Safari does not say that a comma is missing. It says Expected '}' for a missing comma and for an unquoted key, so the message alone does not tell you which. Look at the character before the spot. If a value ends there, add a comma. If a { or a comma is there, the key needs double quotes. See Unquoted property names.

Worth knowing