Critical CSS Budget Calculator
Check inline critical CSS size, unused CSS percentage, compressed weight, and first-response budget.
About This Tool
Inline critical CSS can improve first paint, but too much inline CSS makes the HTML response heavy.
Use this tool to keep above-the-fold CSS focused while moving non-critical rules out of the initial response.
Critical CSS
18.0 KB
Unused CSS
12%
Status
Needs improvement
How to Use
- 1
Enter the values you need or paste your text into the input area.
- 2
Adjust any options, units, or settings for your exact use case.
- 3
Review the result and copy it into your document, workflow, or next task.
Features
Instant Results
Outputs update directly in the browser as you enter values.
Browser-Based Processing
Your inputs are handled locally and are not uploaded for calculation.
Simple Inputs
Clear fields and readable outputs keep repeat tasks fast.
Free to Use
Use the tool immediately with no sign-up or installation.
Common use cases
- ›Decide whether a critical CSS block is small enough to inline.
- ›Estimate the compressed weight added to the first HTML response.
- ›Flag pages where unused above-the-fold CSS is becoming a maintenance problem.
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