How much does resolution affect file size?

[milkydoo]

I've noticed in the various calculators and encoder apps that I've tried, that altering the resolution field does not cause any change in the projected file size.

I always thought that lower resolution means less data, and therefore smaller size, but these calculators don't show it. Is this because they can't project it very well? Is there some way for me to get a ballpark idea?

[poisondeathray]

It doesn't , at least not directly

Filesize = bitrate x running time

But a larger resolution will require more bitrate for it to keep the same level of "quality", and more complex material (e.g. action scenes, lots of movement etc...) will also

[Baldrick]

It's just the video and audio BITRATE and runtime that affects the file size when you calculate the file size.

1000kbit/s 1920x1080 and 1000kbit/s 320x240 = same file size.

But of course will the 1920x1080 look like crap.

[milkydoo]

Ok, that clears it up. Thanks.