Dummy 10 MB CSV File
Generate and download a dummy 10 MB CSV file. The download is exactly 10,485,760 bytes, created in your browser and never uploaded.
Need a different size? Make a dummy CSV file of any size from 7 Bytes to 50 MB.
Testing with a 10 MB CSV file
A 10 MB CSV equals the API Gateway REST payload quota. It is also a good test of whether your importer streams rows or reads the whole file into memory first: with the default 5 rows each row is about 2 MB, and with Rows set to 100,000 it is a long file of short rows.
Import time at this size shows whether progress reporting and request timeouts are configured sensibly.
If your importer reports how many rows it read, compare the figure with the Number of rows you chose. A difference of one usually comes from the header line, which is the first place to look when counts do not match.
- Exact size (binary)
- 10,485,760 bytes
- Decimal equivalent
- 10,000,000 bytes
- Base64-encoded size
- 13,981,016 bytes
- Rows and columns
- 5 rows x 10 columns by default (choose 1 to 1,000,000 rows and 1 to 100 columns in Options)
- Most rows at 10 columns
- 101,501
Exact size and boundary files for 10 MB
Set the unit to B and enter these byte counts to test either reading of 10 MB.
| Limit defined as | One under (should pass) | At the limit | One over (should fail) |
|---|---|---|---|
| Binary 10 MB | One under (should pass) 10,485,759 B | At the limit 10,485,760 B | One over (should fail) 10,485,761 B |
| Decimal 10 MB | One under (should pass) 9,999,999 B | At the limit 10,000,000 B | One over (should fail) 10,000,001 B |
Limits closest to 10 MB
A 10 MB file is over nginx (1 MB), PHP (2 MB) and AWS Lambda (6 MB); exactly at API Gateway (10 MB) and Outlook with Exchange (10 MB); under Outlook with internet accounts (20 MB), Gmail (25 MB) and Cloudflare Free and Pro (100 MB). Sent as base64 text it grows past API Gateway and Outlook with Exchange.
| Limit | Size | Notes |
|---|---|---|
| Amazon API Gateway REST API payload | 10 MB 10,485,760 B | Hard quota for REST APIs. |
| Outlook default attachment limit (Exchange accounts) | 10 MB 10,485,760 B | Administrators can change it. |
| Outlook attachment limit (internet accounts) | 20 MB 20,971,520 B | Per Microsoft Outlook guidance. |
Other dummy CSV file sizes
Smaller: 1 MB CSV. Larger: 50 MB CSV. Or see the full dummy CSV file generator.
Other 10 MB dummy files
The same size in another file type.
10 MB CSV file FAQ
Is the 10 MB CSV file exactly 10 MB?
Yes: 10,485,760 bytes in binary units. For a decimal 10 MB, set the unit to B and enter 10,000,000.
How many rows are in a 10 MB dummy CSV?
5 data rows plus the header by default, because you choose the rows in Options and the size does not change the count. At 10 columns a 10 MB file can hold up to 101,501 rows, and the Number of rows option stops at 1,000,000. The file stays exactly 10,485,760 bytes, with the extra bytes as filler in the last column.
Will a 10 MB dummy CSV open in Excel without losing rows?
Yes, as far as the row limit goes. The file has the rows you choose, at most 1,000,000 plus the header, which is under Excel's 1,048,576-row worksheet limit, so no rows fall past it. No row is cut to reach 10,485,760 bytes.
Will a 10 MB CSV file pass the Amazon API Gateway REST API payload?
Probably not. At exactly 10,485,760 bytes it equals the 10 MB limit in binary units, and a form upload adds a few hundred bytes of multipart boundary and headers, so the body ends up over. Counted in decimal megabytes (10,000,000 bytes) the file is 485,760 bytes over. Test one byte under to see it pass. As base64 it is 13,981,016 characters, over the limit, and that is the size that counts in a JSON body or an email.
Is the file uploaded anywhere?
No. It is generated in your browser and never leaves your device.