Unable to save JSON values


I am new to Postman. My issue is described below. Kindly suggest.

Hit a request, select one JSON variable/property from Response, if that value is > 10, fail the assertion in Tests.

When I am trying to save the JSON property, it’s replying back saying it’s Undefined.

I tried parsing too but didn’t work. Also, I tried the below code which didnt work.

pm.test(“Max Temp greater than 10 validation”,function () {
var jsonData = pm.response.json();

Hey @ArupAcharya

Welcome to the Postman community! :rocket:

Could you share an example of the response body, please?

Without seeing the response I’m just guessing here but it could be something like this:


Thanks @dannydainton. here is the response.


"coord": {

    "lon": -74.01,

    "lat": 40.71


"weather": [


        "id": 800,

        "main": "Clear",

        "description": "clear sky",

        "icon": "01d"



"base": "stations",

"main": {

    "temp": 295.74,

    "feels_like": 294.5,

    "temp_min": 294.26,

    "temp_max": 297.15,

    "pressure": 1028,

    "humidity": 36


"visibility": 10000,

"wind": {

    "speed": 0.69,

    "deg": 216


"clouds": {

    "all": 1


"dt": 1604870456,

"sys": {

    "type": 1,

    "id": 4610,

    "country": "US",

    "sunrise": 1604835312,

    "sunset": 1604871871


"timezone": -18000,

"id": 5128581,

"name": "New York",

"cod": 200



It still fails with below error.
Max Temp greater than 10 validation | AssertionError: expected undefined to be a number or a date

It looks like temp_max is inside the main object so it would be jsonData.main["temp_max"]

It works like a mule.

Thanks very much. Appreciate your quick response. Learnt something tonight. happy to sleep now.

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