Exact File Size PNG Generator for KB and MB Upload Tests

Create an image for file upload testing with a target file size and custom dimensions.

Free to use. No signup or watermark.
Canvas
Live preview
1200 × 800px
Made on your devicePreview fits; export is full size

Exact KB and MB PNG test files for upload validation

Create a PNG with an exact file size to test an upload limit or reproduce a validation issue. Set custom dimensions and a KB or MB target. The generator encodes a new image, then adds a valid PNG data chunk to reach the target when the encoded pixels fit. The size control uses binary units: 100 KB is 102,400 bytes. This workflow pads a test fixture rather than compressing an uploaded photo, and targets must not exceed 20 MiB.

Ways to use the image by file size

Test a file upload size limit.

Prepare image fixtures for a development workflow.

Compare image dimensions with downloaded file weight.

How to create an exact 100 KB PNG for upload testing

This tool pads a valid PNG to a chosen file size. It is useful for upload testing; it does not compress an existing picture to that target.

Understand binary KB and an exact PNG byte target

The size control uses binary kilobytes: 100 KB means 102,400 bytes. The generated PNG is encoded first, then a valid ancillary data chunk fills the remaining space. The padding changes the file length without adding visible pixels or improving the image's quality.

Choose a target that can hold the image

The target must be large enough for the encoded PNG and the padding chunk. A detailed pattern or large canvas may already exceed a small target. Reduce dimensions or simplify the image if that happens. The maximum target is 20 MiB, and this workflow exports PNG only.

Verify the upload requirement in bytes

A website may use decimal KB, rounded labels, or a strict maximum. Compare exact byte counts rather than assuming its label matches this tool's units. Another image optimizer may remove ancillary metadata and shrink the padded file, so use the original download when testing a precise byte threshold.

Need help choosing a file? Read the image format guide or compare common pixel dimensions.

Popular image by file size sizes

Choose a starting point. Every size is fully customizable.

Find more dimensions in the image size guide

Image by File Size: questions & answers

Everything you need before your next download.

Why does image file size differ from its pixel dimensions?

Dimensions count the image pixels. File size depends on the format, compression, and image content, so two images with the same dimensions can have very different file sizes.

Should generated test files be used as production photos?

These images are intended for upload and validation testing. For production content, export the real image at the quality and format required by your project.

Start your next creation with a simple image

Set the mood for a social post, refresh your wallpaper, or give a presentation a clean opening. Pick a canvas and make it yours.

Put your favorite colors on your screen

A soft sunset gradient or a quiet wash of color can make a screen feel like yours. Choose a 4K desktop canvas or a portrait phone size, then build a wallpaper around your own palette.

Give your next presentation a clean opening

Leave room for your ideas with a white canvas, or set the tone with a simple gradient. Start at 1920 × 1080, then add your title in a slide app or use the background for a project cover.