Choose the right calculator
Planning video storage
Use duration and average video plus audio bitrate. Resolution by itself does not determine the file size.
Sending a file
Use file size and upload speed, then allow for less than full throughput. Use download speed for a download.
Printing an image
Start with pixel dimensions and a target pixels-per-inch value to find the physical print dimensions.
Budgeting equipment power
Use average operating draw and run time. A power supply’s maximum rating may differ from actual usage.
Put the numbers to work
The aquarium tool is a separate geometric volume estimate. It uses internal dimensions, actual water height, and displacement; it is not a stocking or dosing guide.