1 MB STL sample file
An STL file of exactly 1,048,576 bytes. It is a valid STL 3D model (stereolithography) file, generated for this site and checked with an independent parser. Use it wherever you need a 1 MB sample, test or dummy STL file.
Download
sample-stl-1mb.stl
1 MB1,048,576 bytes
Download 1 MB STLDirect download. No sign-up and no waiting.
- Type
- model/stl
- SHA-256
ec250a52d945b257d625b553331ecc820340d162dbd04c003cfb862559a04bd8- Direct URL
https://www.sampletestfiles.com/downloads/stl/sample-stl-1mb.stl
What is in this file
One solid of 5,676 triangles forming a height-field surface, each written as a facet with its normal and three vertices. Blank lines before the closing endsolid statement, which ASCII STL ignores, bring the file to the exact size.
| Triangles | 5,676 |
|---|---|
| Encoding | ASCII STL |
| Solids | 1 (terrain) |
| Units | None: STL has no unit of measurement |
| Colour and materials | None |
How the file begins
The opening lines of sample-stl-1mb.stl, exactly as they appear in the file.
solid terrain
facet normal -0.1467 0.6125 -0.7767
outer loop
vertex 0.0000 0.0000 0.0000
vertex 0.0000 0.6341 0.5000
vertex 0.5000 0.1197 0.0000
endloop
endfacet
facet normal -0.1197 0.6298 -0.7675
outer loop
vertex 0.5000 0.1197 0.0000
vertex 0.0000 0.6341 0.5000
vertex 0.5000 0.7291 0.5000
endloopPreview
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
- Finding the first upload limit in a new stack
- Testing 3D model upload for print services
- Checking detection of ASCII and binary files
Testing notes for STL
- The .stl extension is also used for Windows certificate trust lists, which is why some servers label a 3D model application/vnd.ms-pki.stl.
- A binary file may start with the word "solid" in its free-text header, and many do. Detection has to test whether the file length equals 84 plus 50 bytes for each triangle, not just read the first five bytes.
Technical details
| File name | sample-stl-1mb.stl |
|---|---|
| Format | STL (STL 3D model (stereolithography)) |
| Extension | .stl |
| MIME type | model/stl |
| Size | 1,048,576 bytes (1 MB) |
| Kind | Text |
| Signature | 73 6F 6C 69 64 |
| SHA-256 | ec250a52d945b257d625b553331ecc820340d162dbd04c003cfb862559a04bd8 |
| 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 | 3D Models |
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-stl-1mb.stl 'https://www.sampletestfiles.com/downloads/stl/sample-stl-1mb.stl'
sha256sum sample-stl-1mb.stl # Linux
shasum -a 256 sample-stl-1mb.stl # macOSOn Windows, run Get-FileHash sample-stl-1mb.stl -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 STL file?
- One solid of 5,676 triangles forming a height-field surface, each written as a facet with its normal and three vertices. Blank lines before the closing endsolid statement, which ASCII STL ignores, bring the file to the exact size.
- Are the STL samples ASCII or binary?
- The sized samples are ASCII STL, which can be padded to an exact byte count with blank lines. The curated library adds a binary STL file, a unit cube of 12 triangles.