Geekbench released a pre-released version (5.4) of their benchmarking software a short while ago which makes it very easy to benchmark your single board computers and compare them. Of course this might also work with any kind of ARM device.
Right now it works for arm (armv7) and the new RISC-V architecture. It is still a pre-release so it may not work perfectly or show all of your specs or might not even work at all.
Once downloaded extract it (e.g. on linux with tar):
tar xf Geekbench-5.4.0-LinuxARMPreview.tar.gz cd Geekbench-5.4.0-LinuxARMPreview.tar.gz ./geekbench5
This will run geekbench on your device, upload the results to their site and gives you the link to access them.
As for my passively-cooled Raspberry Pi 4:
Geekbench 5.4, https://www.geekbench.com/blog/2021/03/geekbench-54/ (last visited Mar. 17, 2021).