How to compress a PDF that is too big
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You try to email a PDF and it gets refused for being too big. Or you upload it to a form and it says you are over the limit. It usually happens with documents that have photos or scanned pages in them. Compressing it takes under a minute, it is free and there is nothing to install. I will show you how, how to pick the right level, and at the end I will explain why sometimes the file barely shrinks no matter how much you compress it.
Go to iLovePDF
Open your browser and go to i love p d f.com. If it comes up in another language, you can change it from the top right corner. This is the home page with all the tools. The one we want now is Compress PDF. And there we are.
Upload your PDF
Click the red button, pick your document and upload it. You can also drag it straight onto the box, which is quicker. For this example I am using a PDF with photographs that weighs four megabytes: exactly the kind of file that causes trouble when you try to send it.
Pick the compression level
Now look at the panel on the right, because this is where everything is decided. There are three levels. Extreme compression cuts as much as it possibly can, but the images lose quality and you can tell. Recommended compression is the one already selected and the one you should use almost every time: it brings the weight right down without the photos looking bad. And less compression barely touches the file, for when quality matters more than size. My advice: always start with the recommended one, and only if it is still too heavy, try the extreme.
Click "Compress PDF"
With the level picked, click the red button on the right that says "Compress PDF". It takes a few seconds, depending on how heavy the file is and how many images it has.
See how much it dropped
And here is the interesting part. Look at the circle: it tells you exactly how much it dropped. In this case, from four megabytes down to four hundred and forty-nine kilobytes. Ninety per cent less, and the photos still look perfectly fine. Click the download button and the optimised PDF is saved to your downloads folder.
Why sometimes it barely shrinks
Now the part almost nobody explains. If you compress a PDF and the saving is one or two per cent, the tool has not failed: it is that your document has nothing to cut. Compressing a PDF is, basically, lowering the quality of the images. If your file is only text, there are no images to touch, and that is why it barely shrinks. A text PDF that already weighs very little cannot be made smaller, and that is normal. If yours is heavy and still will not shrink, it almost always has scanned pages at a huge resolution, and there the extreme level will make a real difference.
What happens to your files
And the usual, which applies to all these tools. Your file is uploaded to a server so it can be processed, and it is deleted there automatically after a few hours. For holiday photos or an ordinary report there is no problem. But if it is a document with sensitive data, think twice: for that you are better off with a program that works on your own computer. And if you upload it anyway, click the bin when you are done to wipe it there and then.
And that is it: a PDF that was too big, shrunk in under a minute and for free. Remember what matters: start with the recommended compression, and if your file is only text, do not expect miracles.
Common questions
I compressed my PDF and it only dropped 1%. Why?
Because your document is almost all text. Compressing a PDF means lowering the quality of the images, so if there are no images, there is nothing to cut. A text PDF is already compressed out of the box and cannot be made much smaller. It is not a fault in the tool: that file was already at its sensible minimum size.
Which compression level should I pick?
The recommended one, almost always. It brings the weight right down and the images still look fine. Only if the result is still too big is it worth uploading it again and trying the extreme, which cuts more but leaves the photos visibly worse. Going straight for the extreme is ruining the quality for nothing.
Does compressing lose quality?
In the images, always: that is exactly what compression does. At the recommended level the loss is barely noticeable on screen. At the extreme level you can tell, especially if you are going to print the document or zoom into the photos. The text is never touched: it stays selectable and searchable just as before.
Can I compress several PDFs at once?
Yes. Unlike some other tools on the same site, this one takes several files at a time and compresses them all at the same level. If there are several, the result comes back as a zip.
My PDF is still too big for email. What now?
Try the extreme compression first. If it still will not fit, there are two ways out: split the PDF into parts with the split tool and send them separately, or upload it to Google Drive or Dropbox and send the link instead of the file. Most email services refuse attachments over 25 MB.
Is it safe to upload the document?
For an ordinary document, yes: it travels encrypted, is processed on the iLovePDF server and is deleted automatically after a few hours. For documents with sensitive data you are better off with a program that works on your own computer and uploads nothing. If you upload it anyway, click the bin icon when you are done to wipe it from the server there and then.
