Guides

How to get a PDF under an upload size limit like 100 KB or 2 MB

Updated 23.9.2026

To get a PDF under an upload size limit such as 100 KB or 2 MB without making it unreadable, you need to target image resolution, remove unnecessary elements, and apply the right export or compression settings. Immigration, Refugees and Citizenship Canada notes that saving a document as a PDF using the lowest file size setting helps decrease its file size.^[1]

Adjust document and export settings

If you create your document in a word processor or desktop app, you can reduce the file size before you even export it. According to Immigration, Refugees and Citizenship Canada, selecting the 'Minimum size' optimization setting in Microsoft Word reduces PDF size while maintaining clear text and images.^[1] Deleting unnecessary images from the file also helps reduce overall file size.^[1]

For images that remain in the document, saving images at a lower resolution, such as 96 DPI or 150 DPI, can greatly reduce image file size.^[1]

Optimize scanned documents

Scanned files frequently exceed strict portal limits because scanners default to high-resolution color captures. The Department of Trade Industry and Competition advises that lowering the scanning resolution to 150 dpi or 96 dpi and selecting a text setting produces a smaller PDF file.^[2]

In addition, scanning in grayscale or black and white instead of full color drastically reduces the resulting file size.^[2] You can also enable document compression settings on supported scanners or printers to decrease PDF file size further.^[2]

Reduce PDF size in macOS Preview

If you are using macOS, the built-in Preview app offers tools to shrink existing files. In Preview on macOS, a PDF's file size can be reduced by exporting the file using the 'Reduce File Size' Quartz Filter.^[3] Preview allows reducing PDF file size during export by optimizing images for screen viewing and converting images to JPEG compression.^[3] Note that compressing a PDF in Preview may decrease its visual quality, with the final file size and quality varying according to selected options.^[3]

Use an online compression tool

When you need to hit an exact limit such as 100 KB, 200 KB, or 1 MB, you can use Toololo's dedicated PDF compression tool. The tool can aim for a target size such as 100 KB, 200 KB or 1 MB.

It provides two processing modes:

• On this device: The PDF is compressed in the browser and never leaves the computer. This mode handles up to about 100 MB depending on the computer's memory.
• Best compression: The PDF is sent over an encrypted connection to Toololo's server in the EU, compressed and deleted straight away. It accepts PDFs up to 50 MB. With Best compression, text and links stay selectable; only images are re-encoded.

Questions people ask

What scanning settings help keep a PDF under a small file limit?

Lowering the scanning resolution to 150 dpi or 96 dpi and choosing a text setting produces a smaller PDF file.^[2] Scanning in grayscale or black and white instead of full color also drastically reduces file size.^[2]

How can I reduce PDF size in Microsoft Word without making it unreadable?

Selecting the 'Minimum size' optimization setting in Microsoft Word reduces the PDF size while maintaining clear text and images.^[1] Lowering image resolution to 96 DPI or 150 DPI also significantly reduces file size.^[1]

Does reducing PDF file size in Apple Preview affect quality?

Yes. Compressing a PDF in Preview may decrease its visual quality, with final file size and quality varying based on the options you choose.^[3] It reduces file size by optimizing images for screen viewing and converting them to JPEG compression.^[3]