> Probably depends on the platform, I wouldn't be surprised if it was > 200 MB on OS X. But either way, 100 vs 200, same order of magnitude

keep in mind that Qt Creator comes with a full clang for its C++ code model which is already 40-50 megabytes at least ; no decent C++ IDE can skip that.

Regarding the Qt SDK size, what can take gigabytes is installing it for all android & iOS ... ABIs / versions.

for a fast SDK installation experience, I recommend aqtinstall:

    $ pip install aqtinstall
    $ time python -m aqt install 5.15.0 linux desktop -O ~/Qt/
    10,43s user 2,14s system 153% cpu 8,213 total
    $ du -csh ~/Qt/5.15.0
    592M 5.15.0

(but really, just install e.g. qtbase5-dev on Debian systems has 99.9% of what is needed for most GUI desktop apps and is ~13 megabytes: https://packages.debian.org/sid/qtbase5-dev what takes space is 3D engines, webviews, multimedia apis, etc... but an awful amount of apps don't need those)