When to use this calculator
Find a screen’s diagonal from its width and height. Measure the visible display rather than the bezel and use the same units.
Explore the everyday digital measurements calculators for other questions in this topic. For a related calculation, use the Storage Capacity Calculator: Estimate how many equal-size files fit in decimal gigabytes of storage.
PUTTING IT INTO PRACTICE
Screen Diagonal: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| Screen width | 48 |
| Screen height | 27 |
| Result | 55.072679 units |
- Check the input labels and enter the example values above.
- Apply the relationship: Diagonal = √(width² + height²).
- The result is 55.072679 units, rounded for display.
How to interpret your result
Measure the visible display rather than the bezel and use the same units.
Bits and bytes differ by a factor of eight. Decimal MB and GB are different from binary MiB and GiB. A file-capacity estimate should use usable storage rather than a device’s advertised total where possible.
Frequently asked questions
Are MB and MiB the same amount of data?
No. MB is one million bytes; MiB is 1,048,576 bytes. These tools state decimal units where relevant.
How do I use the screen diagonal calculator?
Enter screen width, screen height. The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Diagonal = √(width² + height²).
What should I check before using the result?
Measure the visible display rather than the bezel and use the same units.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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