Browser calculators
Web Trial Lab Calculators
Simple practical calculators for creators, developers, and everyday work. Everything runs in your browser with no upload, account, cookies, or server-side calculation.
Sizing
Aspect Ratio Calculator
Enter a width and height to simplify the ratio, or provide one missing dimension from a known ratio.
How to use aspect ratios
Aspect ratio is width compared with height. Use it when resizing thumbnails, video canvases, screenshots, social posts, and responsive embeds while preserving shape.
Work time
Time Duration Calculator
Calculate elapsed time between two clock values, subtract an optional break, and handle overnight shifts.
Time duration notes
If the end time is earlier than the start time, the calculator treats it as an overnight shift. You can also check the overnight box to make that intent explicit.
Screens
PPI Calculator
Estimate pixels per inch and pixel pitch from screen resolution and diagonal size.
What PPI means
Higher PPI means pixels are packed more tightly. Pixel pitch is the physical size of one pixel, expressed here in millimeters.
Dates
Date Difference Calculator
Count calendar days between two dates with an optional inclusive end date.
FAQ
Calculator FAQ
Are calculations sent to a server?
No. The calculators run locally in the browser. There is no signup, upload, or cookie.
Can I use decimal dimensions?
Yes. Aspect ratio and PPI inputs accept decimal values when that is useful.
How are overnight hours handled?
If an end time is earlier than a start time, the calculator treats the end as the next day. You can also enable the overnight checkbox.