I might sound dumb asking this, but if I download a 2GB file using my cellular data, will it actually use 2GB of my data allowance? I assume that's how data usage is measured, but I'm not entirely sure.
4 Answers
It’s definitely not a 1:1 ratio. Just keep an eye on your usage.
Just a heads up, some carriers might measure differently, using 1000s instead of 1024s. It's rare, but if that’s the case, 2GB for them could mean around 2000MB instead of 2048MB, making it look like more data use.
It'll likely use a bit more than just the 2GB due to some overhead, like packet retransmission.
Yeah, like others said, there is some overhead, so you'll end up using a bit more than the file size itself. That's probably rounded up as well, so keep that in mind.

Related Questions
How to Build a Custom GPT Journalist That Posts Directly to WordPress
Cloudflare Origin SSL Certificate Setup Guide
How To Effectively Monetize A Site With Ads