Size of document for web

[jennyf50536786]

Trying to create a digital ad for web advertising. I create a new document in InDesign and i chose "For web" and for example size 980 x 240 pxl. Then when i export the file to png the size if no longer 980 x 240 but much bigger.... What am i missing? 

If i have a set px size of an ad that i´m supposed to deliver, can´t i create the digital ad in InDesign.... ? 

[Michael Bullo]

Ensure that InDesign is exporting at a resolution of 72ppi and your exported graphic should match the pixel dimensions of your document.

[Michael Bullo]

In case you don't know and it's a potential issue, try not to get hung up on image resolution when creating graphics for the web. You generally only need to be concerned that you are providing images with enough pixels in terms of width and height. The resolution is actually irrelevant. As far as the web is concerned, the following two images, for example, are essentially identical…

Image 1
Width: 1000px
Height: 500px
Resolution: 72ppi

Image 2
Width: 1000px
Height: 500px
Resolution: 300ppi