Live Preview on Canary

Hello Post People!
So we have another awesome Canary release we wanted to let you know about.

So what’s new?
Postman makes it easy to make requests by adding headers that are needed in general and ones that browsers and other popular http clients send.
Last year, we made them visible in the form of temporary headers.
However, we heard from you, our users, that this had created some confusion.

So we are introducing something to help with that, known as Live Preview. We will now show you headers that will be sent and tell you how to configure them. These are the headers that will be added to the requests as a result of your requests configuration, such as an authentication method or request body type selected by you. These are just some first steps we are taking to help improve the user experience and functionality of Postman.

How does this impact me?
Creating requests should be very much the way you have known it to be in the past. We have removed the separated “Temporary Headers” vs. “Headers”, now they are all just “Headers”.
We have changed a few things though.
First is, when you do authentication. We have removed the “Preview” button and now when you add an authentication method to your request, it will always be visible as a header to the request.
This same logic applies to things such as cookies. You will see them as a normal header, however you will not be able to directly edit them. They can be edited through the method they were created from.

The next thing you should know is how these headers work. The final request and any headers that were required for Postman to work is, like always, visible in the Postman Console (which, by the way, we reworked to have better experience and contain a tonne of useful info.)

P.S. - As a side note. These changes are not yet reflected in places such as the code generator until the first time the request has been sent.

So, we would love for you to take this for a test run and let us know what you think.
Please reach out to us with your thoughts and input on this new and upcoming feature.

You can download the Canary builds from here -


Hey everyone,

On top of what @tmccann shared, and while we’re adding more helpers directly in the app to make it easier to manage headers, below are more detailed information on how to manage the headers that are sent with your requests.

Click on each entry to see the details.

How to disable the `cookie` header?

If you want to keep cookies in your request from being stored in the cookie jar, open the Settings tabs in your request and toggle Disable cookie jar to ON.

Show/Hide auto-generated headers

You can now choose whether to display the auto-generated headers or not. Displaying them will allow to edit or disable some of them.

How to disable or override the `Cache-Control` header?

The no-cache header means a cache will send the request to the origin server for validation before releasing a cached copy (learn more).

To disable it, display the auto-generated headers (see first section), hover on the Cache-Control entry, then click Go to settings. You can turn off Send no-cache header from that window.

You can also override the header value by going to the Headers tab of your request, and adding a Cache-Control header with the value you would like (e.g. no-store).

How to disable the `Postman-Token` header?

The postman-token header helps you track requests coming from Postman on your server, if you want to disable it, display the auto-generated headers (see first section), hover on the Postman-Token entry, then click Go to settings. You can turn off Send Postman Token header from that window.

How to override or disable other auto-generated header?

You can override any header added to your request by going to the Headers tab of your request, displaying the auto-generated headers, and either:

In the coming weeks we’ll be releasing additional helper functionality to provide control over your other request headers—we will keep you posted on progress and will update this FAQ accordingly! In the meantime please feel free to share any feedback you have. :slight_smile:



I was able call some APIs with the canary version that I wasn’t able to with the default behavior in the production postman app, so thanks a bunch for working on this. In my case I’m working with some legacy systems and I don’t have control over what headers it is expecting to receive. It turns out postman was handling the cookies in a way that my server wasn’t expecting and the cookie jar disabling setting did the trick.

I see that we have the option to override anything, but I would appreciate being able to tell postman to not send a header at all. For example I can’t seem to tell postman to not send Accept-Encoding, User-Agent, or Host. I was only attempting to do this to debug my situation (which seems resolved now), but I don’t see why the app should force us to include headers if we don’t want them. I tried setting them to an empty string but that resulted in other issues.


Hi @nloyer,

Great to hear using the canary version helped with your issue, and thanks for the feedback! I’ll forward that to the team. :slight_smile:

Thanks again for the feedback. We are rolling out our next update in a week’s time. That would allow you to remove all headers.

Unfortunately, there will still be two headers that you can overwrite, but not completely remove … host and connection. Thankfully these will be the least likely ones to get in the way of requesting. There are plans to address them some time in future after we overcome some underlying technical limitations.


Hey everyone!

We’ve published new updates to Live Preview giving you even more control over the headers that are sent with your request. Update your Postman Canary or get the latest version here:

We’ve updated the FAQ above to reflect the new actions you can take on auto-generated headers: Live Preview on Canary

We’re looking forward to hear your feedback on these improvements!

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Live Preview is now available in the production app (from 7.21.0), read more about it here!

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