Response size in Postman - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the response size in bytes?

You send a GET request to an API endpoint that returns the JSON: {"name":"Alice","age":30}. Postman shows the response size as 25 bytes. What does this size represent?

A The size of the response body in kilobytes, rounded to the nearest integer.

B The size of the response headers only, excluding the body.

C The size of the response body compressed with gzip.

D The total size of the response body in bytes, including all characters in the JSON string.

💡 Hint

Think about what Postman counts as response size when showing it in the interface.

Postman shows the response size as the total number of bytes in the response body, including all characters in the JSON string. It does not count headers or compressed sizes unless explicitly noted.

❓ assertion

intermediate

Which assertion correctly checks response size?

You want to write a test in Postman to verify that the response size is less than 1 KB. Which assertion code snippet is correct?

A pm.test('Response size is less than 1KB', () => { pm.expect(pm.response.size()).to.be.below(1024); });

B pm.test('Response size is less than 1KB', () => { pm.expect(pm.response.responseSize).to.be.below(1024); });

C pm.test('Response size is less than 1KB', () => { pm.expect(pm.response.size).to.be.below(1024); });

D pm.test('Response size is less than 1KB', () => { pm.expect(pm.response.body.size()).to.be.below(1024); });

💡 Hint

Check the Postman API for the correct method to get response size.

The correct method to get the response size in Postman scripts is pm.response.size(). The other options use incorrect properties or methods.

🔧 Debug

advanced

Why does this Postman test fail to check response size?

Consider this Postman test code:

pm.test('Response size check', () => { const size = pm.response.responseSize; pm.expect(size).to.be.below(2048); });

Why does this test fail even when the response size is below 2048 bytes?

Postman

pm.test('Response size check', () => { const size = pm.response.responseSize; pm.expect(size).to.be.below(2048); });

A The test fails because pm.expect requires a callback function, not a direct value.

B The response size is measured in kilobytes, so 2048 is too small a limit.

C pm.response.responseSize is undefined; the correct method is pm.response.size() to get the response size.

D pm.response.responseSize returns the size of headers only, not the body.

💡 Hint

Check the Postman scripting API for the correct property or method to get response size.

pm.response.responseSize is not a valid property. The correct way to get the response size is by calling pm.response.size() method.

🧠 Conceptual

advanced

What does Postman include in response size measurement?

When Postman shows the response size for an API call, which parts are included in this size measurement?

A The combined size of response headers and body in bytes.

B Only the response body size in bytes, excluding headers and status line.

C Only the size of response headers in bytes, excluding the body.

D The size of the response body compressed with gzip if compression is enabled.

💡 Hint

Observe what the 'Size' field shows in the Postman response view.

Postman shows the response size as the size of the response body in bytes, excluding headers. Headers size is shown separately.

❓ framework

expert

How to programmatically log response size in Postman tests?

You want to log the response size in bytes to the Postman console after each request. Which code snippet correctly does this?

A console.log(`Response size: ${pm.response.size()} bytes`);

B console.log('Response size: ' + pm.response.responseSize + ' bytes');

C console.log(`Response size: ${pm.response.body.size} bytes`);

D console.log('Response size: ' + pm.response.getSize() + ' bytes');

💡 Hint

Check the Postman scripting API for the method that returns response size.

The method pm.response.size() returns the response size in bytes. Other options use invalid properties or methods.