10 KB CSS sample file
A CSS file of exactly 10,240 bytes. It is a valid Cascading Style Sheets file, generated for this site and checked with an independent parser.
Download
sample-css-10kb.css
10 KB10,240 bytes
Download 10 KB CSSDirect download. No sign-up and no waiting.
- Type
- text/css
- SHA-256
40e17ba3b9484a67b67f38ad8626e541f5d8385bba4fc45b5226666215acae09- Direct URL
https://sampletestfiles.com/downloads/css/sample-css-10kb.css
What is in this file
A :root block with custom properties, a body rule and 104 class rules. A closing comment brings the stylesheet to the exact size.
| Rules | 106 |
|---|---|
| Features | Custom properties, class selectors, rem and px units |
| Encoding | UTF-8 (ASCII characters only) |
How the file begins
The opening lines of sample-css-10kb.css, exactly as they appear in the file.
/* SampleTestFiles sample CSS file (10 KB) */
:root {
--ink: #16202b;
--paper: #fafbfc;
}
body {
color: var(--ink);
background: var(--paper);
font-family: system-ui, sans-serif;
}
.sample-1 {
color: #ebebeb;Preview
Shows the file contents.
Where 10 KB matters
A 10,240-byte file that still arrives in the first round trip of a new connection. These are the default limits a file of this size is useful for testing:
| System | Limit | Note |
|---|---|---|
| TCP initial congestion window | About 14.6 KB (10 segments) | A 10 KB response fits in the first flight of packets; the 25 KB sample does not. |
| nginx and Apache request headers | 8 KB per header line by default | Data this large must go in the request body. |
| webpack asset modules | 8 KB by default | Assets over the threshold are emitted as files instead of data URIs. |
Use this file for
- Checking thumbnail and icon handling
- Testing code editors and syntax highlighters
- Testing minifiers and bundlers
Testing notes for CSS
- With X-Content-Type-Options: nosniff, browsers refuse a stylesheet that is not served as text/css.
Technical details
| File name | sample-css-10kb.css |
|---|---|
| Format | CSS (Cascading Style Sheets) |
| Extension | .css |
| MIME type | text/css |
| Size | 10,240 bytes (10 KB) |
| Kind | Text |
| SHA-256 | 40e17ba3b9484a67b67f38ad8626e541f5d8385bba4fc45b5226666215acae09 |
| Created | 2026-10-10 |
| Validation | Exact size, signature bytes and structure checked when the file was generated |
| Preview | Available on this page |
| Source | Generated for this site; not copied from elsewhere |
| Licence | Free to use, modify and redistribute (terms) |
| Category | Code |
Validated for expected format and integrity. As with any download, scan the file with your own security tools before opening it. How files are made and checked
Download from the command line and verify
Fetch the file with curl, then compare its checksum with the SHA-256 value above.
curl -o sample-css-10kb.css 'https://sampletestfiles.com/downloads/css/sample-css-10kb.css'
sha256sum sample-css-10kb.css # Linux
shasum -a 256 sample-css-10kb.css # macOSOn Windows, run Get-FileHash sample-css-10kb.css -Algorithm SHA256 in PowerShell. A matching value proves that the download is complete and unaltered.
Related files
Questions about this file
- Is this file exactly 10 KB?
- Yes. It is 10,240 bytes, which is 10 KB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
- What is inside the 10 KB CSS file?
- A :root block with custom properties, a body rule and 104 class rules. A closing comment brings the stylesheet to the exact size.
- What do the sample stylesheets contain?
- Custom properties, a body rule and a long list of class rules, with no @import rules or external URLs.