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PDF (Portable Document Format) is a universal document format you can open in all PDF readers. So this is a good format for email document attachments. However, there’s a file size limit on what you can attach to emails. If you attach multiple PDFs that exceed the maximum file size, you can compress them to reduce their file size as follows.
4dots Free PDF Compressor is a freeware package you can add to Windows 10, and earlier platforms, from this page. Press the DOWNLOAD NOW button there to save the software’s setup that you can can add the program to Windows with. Open the utility’s window in the snapshot below.
You can select either Add File(s) and Add Folder to open a specific PDF or a folder that contains them. Then it will open the PDF in the software’s window as below. Note that you can also compress a batch of PDFs with this software.
Select an output folder, or path, by pressing the folder button at the bottom of the window. If you don’t choose a specific folder, it will save the compressed PDF in the same path as the original. Click the Compress Images check box and drag the bar further right to retain more image quality. Then press the Compress button at the top of window to cut the selected PDFs down to size.
Open the folder you saved the compressed document to to check its new size. You could get quite a reduction in megabytes. For example, I compressed a PDF from 1.7 MB to 338 KB, which is less than a third of the original file size.
You can also compress a PDF without any extra software. There are a few websites you can compress PDFs from. Click here to open the Smallpdf page below.
Click Choose file to select a PDF document to compress. Then wait for the file to compress, and save the compressed file to Windows by clicking Download File Now. The website page will tell you what the new file size is as below.
So now you can compress PDFs in Windows 10 with the 4dots Free PDF Compressor software or from the Smallpdf website. Both can considerably reduce PDF document sizes, which might be a good way to free up some storage space on the hard disk.