1 MB CSS sample file
A CSS file of exactly 1,048,576 bytes. It is a valid Cascading Style Sheets file, generated for this site and checked with an independent parser.
Download
sample-css-1mb.css
1 MB1,048,576 bytes
Download 1 MB CSSDirect download. No sign-up and no waiting.
- Type
- text/css
- SHA-256
e2e13364f1c12b319ff20dbd63e959f93494984fa483cee3c49c727fbad662a2- Direct URL
https://sampletestfiles.com/downloads/css/sample-css-1mb.css
What is in this file
A :root block with custom properties, a body rule and 10,642 class rules. A closing comment brings the stylesheet to the exact size.
| Rules | 10,644 |
|---|---|
| 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-1mb.css, exactly as they appear in the file.
/* SampleTestFiles sample CSS file (1 MB) */
:root {
--ink: #16202b;
--paper: #fafbfc;
}
body {
color: var(--ink);
background: var(--paper);
font-family: system-ui, sans-serif;
}
.sample-1 {
color: #e3b505;Preview
Shows the first 64 KB of the file.
Where 1 MB matters
A 1,048,576-byte file: exactly the default upload limit of nginx, Spring Boot and Next.js. These are the default limits a file of this size is useful for testing:
| System | Limit | Note |
|---|---|---|
| nginx | 1 MB by default (client_max_body_size) | A multipart upload of this file exceeds the limit by the size of the form boundaries. |
| Spring Boot multipart | 1 MB per file by default (max-file-size) | A file of exactly 1 MB is at the limit. |
| Next.js API routes and Server Actions | 1 MB by default | Larger bodies need the size limit raised in configuration. |
| Cloud Firestore documents | 1 MiB (1,048,576 bytes) | The same number of bytes as this file. |
| Apache Kafka messages | About 1 MB by default | Brokers reject larger records unless message.max.bytes is raised. |
Use this file for
- Download tests on mobile connections
- Checking asset pipelines and caching
- Testing code editors and syntax highlighters
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-1mb.css |
|---|---|
| Format | CSS (Cascading Style Sheets) |
| Extension | .css |
| MIME type | text/css |
| Size | 1,048,576 bytes (1 MB) |
| Kind | Text |
| SHA-256 | e2e13364f1c12b319ff20dbd63e959f93494984fa483cee3c49c727fbad662a2 |
| 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-1mb.css 'https://sampletestfiles.com/downloads/css/sample-css-1mb.css'
sha256sum sample-css-1mb.css # Linux
shasum -a 256 sample-css-1mb.css # macOSOn Windows, run Get-FileHash sample-css-1mb.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 1 MB?
- Yes. It is 1,048,576 bytes, which is 1 MB in the binary units that operating systems and server limits use (1 KB = 1,024 bytes).
- What is inside the 1 MB CSS file?
- A :root block with custom properties, a body rule and 10,642 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.