Create and preview a sample PNG image
Choose the byte size of a generated raster image for PNG upload tests. Preview the result before saving; dimensions can change with the requested size.
1 MB = 1,000,000 B · 1 MiB = 1,048,576 B
Advanced: test an upload limit
Enter the byte limit above, then choose one byte below, the exact limit or one byte above. Each choice uses the same base: 10,485,760 B. Generate and download each file to test your endpoint.
What to test with a PNG fixture
Decode the generated PNG and check its dimensions and byte count separately. Include transparency and pixel-content fixtures when those features matter to your application.
Convert image format · Resize image dimensions · JPG upload fixture
Choose a size here
These options set the generator above. Separate size guides explain how to test a particular upload boundary.
Guides for specific upload limits
File structure and testing limits
A generated raster with valid PNG chunk CRCs. Pixel dimensions grow with the target size; a tEXt chunk fills the remainder. Size is not a promise of photographic content.
Format reference: W3C PNG specification.
This generator assembles the file in your browser; file content is not sent to a server. Site analytics may make network requests. Office ↔ PDF conversion uses a separate server workflow. Data processing and privacy.
Measured regression fixture (2026-10-13): 1,048,576 bytes. Validation method and limits.
Technical notes for every format · Guide to testing file upload limits
Related tools: Image Convert · Resize Image · Compress Image.
Questions
How small can a PNG file be?
About 288 bytes. Below that the format cannot carry its mandatory structure, let alone padding.
Does a bigger PNG necessarily have more pixels?
No. The generator chooses image dimensions and uses a tEXt chunk to complete the requested size. Re-encoding the image can remove that padding and change the saved byte count.
Can I ask for an unusual size?
Any byte count above the minimum works — for example 3,145,728 bytes (exactly 3 MB) or 27.5 MB. Drag the caliper or type the number.
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