Website Page Weight Calculator

Work out website page weight instantly with clear inputs, formula shown and shareable results.

About Website Page Weight Calculator

Page weight is the sum of every transferred asset, and transfer time is that weight in kilobits divided by the connection speed in kilobits per second. Images and fonts usually dominate, which is why compressing them beats minifying JavaScript for most sites even though the latter gets more attention.

Formulas

Total weight

total KB = HTML + CSS + JavaScript + images and fonts

Transfer time

seconds = total KB x 8 / connection kbps

Worked example

With the default values below, Website Page Weight Calculator returns Total page weight of 1,360.0. Change any input above and every figure here is recalculated in your browser.

Inputs used

HTMLminimum 0 KB: 30 KB
CSSminimum 0 KB: 80 KB
JavaScriptminimum 0 KB: 350 KB
Images and fontsminimum 0 KB: 900 KB

Results

Total page weight: 1,360.0 KB
Page weight in megabytes: 1.3281 MB
Share that is images and fonts: 66.18%
Transfer time on a 5 Mbps connection: 2.176 s

Step by step

1Values used
2Total weight
3Transfer time
4Total page weight= 1,360.0 KB
5Page weight in megabytes= 1.3281 MB
6Share that is images and fonts= 66.18
7Transfer time on a 5 Mbps connection= 2.176 s

Assumptions and limits

The result is derived only from the 4 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 4 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 the Website Page Weight figure worked out?

total KB = HTML + CSS + JavaScript + images and fonts. Page weight is the sum of every transferred asset, and transfer time is that weight in kilobits divided by the connection speed in kilobits per second.

Why does this matter?

Images and fonts usually dominate, which is why compressing them beats minifying JavaScript for most sites even though the latter gets more attention.

What do I need to enter?

Enter html, css, javascript, images and fonts. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.