But leaks don't necessarily show how the phone will fit in our hands, pockets or bags. That's why well-known tipster OnLeaks created renderings based on the rumored sizes -- letting you compare them to other phones you might have held before.
There are plenty of people who buy phones based on size alone -- I've got some farsighted relatives, but I won't name names -- who may find these visual guides handy.
Just keep in mind that exact sizing of the S8 and S8 Plus is still unconfirmed, so take these renders with a grain of salt.
Or if you're considering ditching your iPhone 7 for the new Galaxy, OnLeaks has you covered with this GS8 and iPhone side-by-side below:
According to the images, the Galaxy S8 seems like it'll be slightly taller and skinnier than the Huawei P10 and the Google Pixel, but shorter than the LG G6. The Galaxy S8 Plus seems to measure right in between the iPhone 7 Plus and Nexus 6P in terms of height, but is skinnier than both.
We tried asking Samsung, but it declined to tell us the exact sizes of the new phones.
Editors' note: Tune in to watch the Galaxy S8 announcement live with CNET on March 29, starting at 7:30 a.m. PT/10:30 a.m. ET.