Desktop Page Speed Calculator

Estimate desktop page load time and the effect of optimisation measures.

About Desktop Page Speed Calculator

On a fast desktop connection JavaScript execution often exceeds transfer time, so shipping less code matters more than compressing it further. Compression applies only to text resources. Once bandwidth is plentiful, page speed becomes a CPU problem rather than a network one, which changes the optimisation priorities entirely.

Formula

Desktop Page Speed

Load time = server time + compressed transfer time + JavaScript execution time

compression: Text assets typically compress 60 to 80 per cent with gzip or brotli

Worked example

With the default values below, Desktop Page Speed Calculator returns Estimated Load Time of 0.978. Change any input above and every figure here is recalculated in your browser.

Inputs used

Page weightminimum 0 KB: 2,400 KB
Connection speedminimum 0.01 Mbps: 60 Mbps
Server response timeminimum 0 ms: 250 ms
JavaScript execution timeminimum 0 ms: 600 ms
Saving from compressionaccepts 0–100 %: 60 %

Results

Estimated Load Time: 0.978 s
Compressed Transfer Size: 960.0 KB
Transfer Time: 0.128 s
JavaScript Execution Time: 0.600 s
Rating: Fast

Step by step

1Values used
2Desktop Page Speed
3Estimated Load Time= 0.978 s
4Compressed Transfer Size= 960.0 KB
5Transfer Time= 0.128 s
6JavaScript Execution Time= 0.600 s
7Rating= Fast

Assumptions and limits

The result is derived only from the 5 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is Desktop Page Speed calculated?

Load time = server time + compressed transfer time + JavaScript execution time On a fast desktop connection JavaScript execution often exceeds transfer time, so shipping less code matters more than compressing it further. Compression applies only to text resources.

Why does Desktop Page Speed matter?

Once bandwidth is plentiful, page speed becomes a CPU problem rather than a network one, which changes the optimisation priorities entirely.

What values do I need to enter?

This calculator takes 5 inputs: Page weight, Connection speed, Server response time, JavaScript execution time, Saving from compression. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.