When disk size was measured in Megabytes and network bandwidth even less, size of files really mattered. When non-floppy floppy disks were sized in 1.something MB, IOMega Zip drives promised 100x as much storage for only a few times the outlay.

The dramatic growth in capacity and drop in cost of storage has radically outpaced Moore’s law, where a gigabyte of disk storage might have cost $100 in 1997 and only $10 by the year 2000. Nowadays, if you bought your gigs on a spinny platter, they’d cost you less than $0.01 each. For most end users, solid state storage has largely replaced the traditional hard disk and even with 10x performance, the price is still only a few cents per GB.

That said, storing data in the cloud costs money over the long term, and has a potentially negative environmental impact – a Stanford report from a few years ago estimated that saving and storing 100GB in the cloud for a year costs the equivalent of 0.2 tonnes of CO₂, or about the same as a one-way flight from Seattle to San Francisco. So reducing unnecessary cloud storage can be worthwhile.

If you’re writing an email in Outlook, you can see the current size from the File | Info menu.

In Word, Excel and PowerPoint, you can see the document size and other useful info in the same place (varying details depending on which application).

A previous Tip dealt with the scourge of bloating PowerPoint files, where it’s not uncommon to have unnecessary large images lurking within the template you’re using, but there’s a simple trick that’s common across all Office apps – compressing picture size.

Especially if you’re embedding photos from a phone or even screen-grabs from a high-res display, individual files can be in the multi-megabyte* category. In many cases, you might resize your image so doesn’t take up such a huge part of your document, but the app will still be storing the full resolution of the image – including any bits you’ve cropped out – behind the scenes.

To compress pictures in your document – and let’s use PowerPoint as an example given that it’s the chief culprit – simply select an image and in the Picture Format menu which appears, choose the Compress Pictures option.

This will let you determine the level of detail to keep for this image – if it’s a simple presentation, then it probably doesn’t need a very high definition picture. You also select whether to keep or discard any cropped areas, and importantly, whether to apply to just this one or by clearing the top option, applying to all images in the file.

Try taking any large PowerPoint file, delete cropped areas and apply Web or Print resolution to all images, and you might see it drop to 10% of its previous size.

The Compress Pictures option is also available from the folder picker in the old File | Save As dialog, and there are other options to change the default resolution available from within the File | Options menu.

*Remember kiddos, there are 1000 MB in one GB; smart alecs might believe that a kilobyte would be 210 bytes – 1024 – but for 25 years international standards have defined that as a kibibyte or KiB, trying to assert with less ambiguity that a kilobyte is actually 1000 bytes, therefore a Gigabyte is 1,000 x 1,000 x 1,000 = 1,000,000,000 bytes, whereas a Gibibyte – srsly – is 1,0243, or 1,073,741,824 bytes).