File Size Calculator
Have many files of a similar size? Enter how many there are and how big each one is. This tool adds them up and shows the total in the unit that fits.
Enter a count and a file size to see the total.
Totals use decimal units, where 1 GB is 1000 MB. If your files vary in size, use the average size of one for a close estimate.
How It Works
Type the number of files, then the size of one file and its unit. The total updates as you type.
The math is a plain multiply: count times size each. The result then rolls up into KB, MB, GB, or TB so you read a clean figure.
This is the general size estimator. For a single video where you know the bitrate and length, use the video file size calculator instead.
The Formula
Each file size converts to bytes first. A 4 MB photo is 4,000,000 bytes.
Multiply by the count: 500 photos at 4 MB each is 2,000,000,000 bytes.
That total then shows in the largest sensible unit, so 2,000,000,000 bytes reads as 2 GB.
Worked Example
You shot 500 photos and each one is about 4 MB.
500 times 4 MB is 2000 MB.
Rolled up, that is 2 GB, which tells you the memory card or upload you need.
Common Uses
- Sizing a backup before you copy a folder of similar files.
- Checking if a batch of photos fits on a memory card.
- Planning cloud space for a set of documents or exports.
- Estimating an upload of many files of roughly equal size.