CSS usage
See the size and share of CSS used during the check, by page and stylesheet. Styles not used in this run may be needed after an interaction or on another page.
Online CSS audit
Find out how much CSS a page loads, which styles were used during the check, and where rules repeat. Review colors, fonts, layering, and errors in one report.
Result format
The report shows CSS sources, metrics, and signals
Use the report to inspect CSS size and usage, then review colors, fonts, layering, and validation errors.
Illustrative data to explain the report. Your page results appear after a scan.
Stylesheet sources
Compare external stylesheets with styles embedded in the page. Each source includes its size and the amount of code used or unused during the check.
| Source | Type | Usage | Unused |
|---|---|---|---|
| app.css | external | 48 KiB / 72 KiB | 72 KiB · 60% |
| components.css | external | 32 KiB / 8 KiB | 8 KiB · 20% |
| inline styles | inline | 6 KiB / 2 KiB | 2 KiB · 25% |
- Source
- app.css
- Type
- external
- Usage
- 48 KiB / 72 KiB
- Unused
- 72 KiB · 60%
- Source
- components.css
- Type
- external
- Usage
- 32 KiB / 8 KiB
- Unused
- 8 KiB · 20%
- Source
- inline styles
- Type
- inline
- Usage
- 6 KiB / 2 KiB
- Unused
- 2 KiB · 25%
Start with the stylesheet source and a repeated declaration. Check whether the repetitions belong to the same component and state. Edit the source, then compare a new report.
What we check
A complete CSS inventory instead of generic advice
The report brings together stylesheet sources and sizes, code usage, selector priority, repeated declarations, design values, and validation errors.
Size and sources
We collect total CSS size, the number of stylesheet sources, and separate counts for inline and external stylesheets.
Selector specificity
Compare minimum, average, and maximum selector specificity, which helps determine rule priority. Review the most complex selectors separately.
Repeated declarations and !important
See the number of rules, selectors, and declarations, repeated property-value pairs, and examples that use !important.
Media queries and prefixes
We show the most frequent media queries and count CSS properties with vendor prefixes: -webkit-, -moz-, -ms-, and -o-.
Colors, fonts, z-index, and errors
The report outputs unique color values, detected font-family values, numeric z-index values, and examples of CSS validation errors.
How it works
From URL to a full CSS summary for the page
Enter a page URL. Milten opens it in a browser, collects its stylesheets, and prepares a report. No build integration is required.
Load the page and collect CSS
The report lists the checked URL, report date, and style sources. It separates styles embedded in the page from external stylesheets.
Measure CSS usage and selector priority
See how much CSS was used, how many rules and declarations were found, and which selectors have the highest specificity.
Build tables for CSS review
Review repeated declarations, !important, media queries, vendor prefixes, colors, fonts, layering, and CSS errors.
FAQ
Frequently asked questions about CSS audit
Answers about CSS usage, selector priority, !important, report contents, and check duration.
How does unused CSS affect speed?
The browser downloads, parses, and applies CSS before rendering the page. The more unnecessary rules there are, the higher the risk of first-render delays and the harder the interface is to maintain.
Why review selector specificity?
Specificity helps determine which selector takes priority when CSS rules conflict. Very specific selectors make later changes harder because overriding them requires stronger rules.
Should every !important declaration be removed?
No. !important changes a declaration's priority and can be intentional. The report shows where to investigate. Review the cascade and component states before replacing it.
What data will be in the report?
The report includes the URL and date, stylesheet sources and sizes, code usage, selectors and their specificity, repeated declarations, !important, media queries, vendor prefixes, colors, fonts, layering, and CSS errors.
How long does a page check take?
A single-page check usually takes less than a minute. Duration depends on resource count, network conditions, and how long the page takes to stabilize after loading.
Related services
What to check next to this service
JavaScript check
Check JavaScript files, loading errors, and code unused during loading. Find scripts that need further investigation.
OpenHTML check
Find HTML errors and an overly complex page structure. The report identifies the affected elements.
OpenDesign values
Collect page colors, fonts, sizes, and spacing. Get a list of values to use when working on the design.
OpenAccessibility
Find accessibility issues with an automated check. Get recommendations; a full accessibility assessment also needs manual checks.
Open