This is a very (very) rudimentary calculator for estimating the temperature of a component on a PCB. It is based off of a talk I gave at the 2019 Hackaday Supercon.
A couple of notes before you use it- I make some pretty generous assumptions, so accuracy may vary. Also, copper weight has basically no effect on the chip temperature since it’s so conductive. I left it in anyway in case you want to experiment with a material that’s not copper (you would need to change the thermal conductivity too).
All relevant math can be found in the presentation from my talk here.
Free convection (no moving air/fan) can be approximated with a heat transfer coefficient (h) of 5-10 W/m^2K, and forced convection in air is generally up around 10-200 W/m^2K.
Please note that is calculator is provided for reference purposes only- I can’t guarantee it’s results, and you should always validate through careful testing. I’m not responsible if you break/burn/melt things (people included)!