Laptop size explained: inches, centimetres and the bag that fits
Amalia
Laptop size is the diagonal of the screen, measured corner to corner and quoted in inches. It is not the width of the laptop, and it is not the size of the bag you need. A 15.6-inch laptop has a 39.6 cm screen diagonal, but the machine itself is narrower than that. To choose a bag, you need the laptop's real width and depth in centimetres, then a bag whose own measurements are larger.
This guide gives the conversions, the official dimensions of the current MacBooks, and a worked check against the measurements of our women's laptop bags and work totes.
In this guide:
- What does laptop size mean?
- Common laptop sizes in inches and centimetres
- MacBook dimensions in cm
- How to measure your laptop
- What size laptop bag do you need?
- Which of our bags fit which laptop
- Frequently asked questions
What does laptop size mean?
Laptop size means the diagonal length of the screen, from one corner to the opposite corner. Manufacturers quote it in inches, even in the UK and Australia. Apple's own specification page says it plainly: "Screen size is measured diagonally."
Two things follow from that. First, the laptop size says nothing about the frame around the screen, which is why two "14-inch" laptops can differ in width. Second, the diagonal is always longer than the width of the laptop. A laptop sold as 16-inch does not need a 16-inch-wide bag. It needs a bag a little wider than the laptop's actual body, which is a separate figure on the manufacturer's specification sheet.
Laptop size is also rounded in the name. Apple's current 13-inch MacBook Air has a 13.6-inch display, and the 16-inch MacBook Pro has a 16.2-inch display. The name on the box is a family name; the specification sheet is the measurement.
Common laptop sizes in inches and centimetres
One inch is 2.54 cm, so converting a laptop size to centimetres is a single multiplication. The table below converts the screen sizes you will see most often on laptop listings. Remember that these are screen diagonals, not laptop widths.
| Laptop size (screen diagonal) | Diagonal in cm |
|---|---|
| 11.6 inches | 29.5 cm |
| 13.3 inches | 33.8 cm |
| 14 inches | 35.6 cm |
| 15.6 inches | 39.6 cm |
| 16 inches | 40.6 cm |
| 17.3 inches | 43.9 cm |
Two laptops with the same diagonal can still have different bodies, because the frame around the screen varies from one model to the next. That is why the next step is always the specification sheet.
MacBook dimensions in cm
Here are the MacBook dimensions from Apple's UK specification pages for the current MacBook Air and MacBook Pro. Width is the side-to-side measurement, depth is front to back, and height is the thickness when closed.
| Laptop | Display (diagonal) | Width | Depth | Height |
|---|---|---|---|---|
| MacBook Air 13-inch | 13.6 inches | 30.41 cm | 21.5 cm | 1.13 cm |
| MacBook Air 15-inch | 15.3 inches | 34.04 cm | 23.76 cm | 1.15 cm |
| MacBook Pro 14-inch | 14.2 inches | 31.26 cm | 22.12 cm | 1.55 cm |
| MacBook Pro 16-inch | 16.2 inches | 35.57 cm | 24.81 cm | 1.68 cm |
Checked 4 November 2026 on Apple's MacBook Air specifications page and on Apple's MacBook Pro specifications page. Apple updates its range regularly, so check the page for your exact model if it is older.
The useful figure for a bag is the width. A 16-inch MacBook Pro is 35.57 cm wide, so it needs a bag measuring more than 35.57 cm across, plus some room for the lining and a sleeve if you use one.
How to measure your laptop
You can find your laptop size in two ways: read it from the model name, or measure it. Reading it is more reliable, because the specification sheet also gives the body dimensions you need for a bag.
- Find the model name. It is printed on the box, on the invoice, or on the label underneath many laptops.
- Look up the manufacturer's specification page for that model. Note the display size and the width, depth and height in centimetres.
- If you have no model name, measure the screen. Use a tape measure from the bottom-left corner of the visible screen to the top-right corner. Do not include the frame around the screen.
- Divide the result in centimetres by 2.54 to get inches. A 39.6 cm diagonal is a 15.6-inch laptop.
- Measure the closed laptop for the bag. With the lid closed, measure the width side to side and the depth front to back. These two figures decide which bag fits.
Measuring the closed laptop is the step that is easiest to skip. It is also the only measurement the bag cares about.
What size laptop bag do you need?
The laptop bag you need is one whose width and height are both larger than your laptop's width and depth. Laptop bags are usually sold by the laptop size they take ("fits a 15-inch laptop"), but the honest check is centimetres against centimetres.
Three practical points make the difference between a laptop that fits and one that only nearly fits:
- A listed bag size may be measured on the outside. The lining, seams and any padding take up some space, so a laptop within a centimetre of the bag's width is a tight fit.
- A sleeve or case adds width. If you carry the laptop in a sleeve, measure the sleeve, not the laptop.
- The rest of the day takes room too. A bag that holds the laptop and nothing else is a laptop case. For work or uni, look at depth as well: a water bottle and A4 papers need it.
Which of our bags fit which laptop
Here is the check done for four of our bags, using the dimensions on each product page and Apple's figures above. We compared the laptop's width and depth with the bag's two largest measurements. Our product pages do not say whether these are inside or outside measurements, so read a small margin as "tight", not "comfortable".
| Bag | Product page says it fits | Dimensions (cm) | MacBook Air 13 | MacBook Pro 14 | MacBook Air 15 | MacBook Pro 16 |
|---|---|---|---|---|---|---|
| Torino | 13″ laptop, A5 notebook | 31 × 14 × 25 | Tight (0.6 cm spare in width) | No | No | No |
| Capri | 14″ laptop, A4 documents | 33 × 24 × 12 | Yes | Yes | No | No |
| Genova | 15.6″ laptop, A4 documents | 45 × 18 × 28 | Yes | Yes | Yes | Yes |
| Firenze | 17″ laptop, A4 documents | 51 × 40 × 30 | Yes | Yes | Yes | Yes |
The Torino is the interesting case. Its product page lists a 13-inch laptop, and a 13-inch MacBook Air (30.41 cm wide) goes in on paper, with 0.6 cm to spare on the listed width. A 14-inch MacBook Pro, at 31.26 cm, is wider than the bag itself.
The Torino: for a 13-inch laptop and an A5 notebook
The Torino is a compact vegan leather work tote, 31 × 14 × 25 cm, with an organised multi-pocket interior. It suits a small laptop and a tidy day, not a 15-inch machine.
The Capri: for a 14-inch laptop
The Capri is a structured vegan leather handbag, 33 × 24 × 12 cm, with a single wide shoulder strap. On paper it takes a 14-inch MacBook Pro with 1.7 cm to spare in width, but not a 15-inch MacBook Air.
The Genova: for a 15.6-inch or 16-inch laptop
The Genova is a vegan leather work bag, 45 × 18 × 28 cm, carried on the shoulder or by hand. Its product page lists a 15.6-inch laptop, and its width leaves more than 9 cm beyond a 16-inch MacBook Pro. At 45 cm wide, it is a lot of bag for a 13-inch laptop on its own.
If your laptop sits in a tote rather than a dedicated laptop bag, our guide on whether you can put a laptop in a tote bag covers what to look for.
Frequently asked questions
What are the common laptop sizes?
Common laptop sizes run from about 11 to 17 inches, measured diagonally across the screen, with 13.3, 14, 15.6 and 16 inches among the sizes you will see most on listings. Apple's current MacBooks have 13.6, 14.2, 15.3 and 16.2-inch displays, sold as 13, 14, 15 and 16-inch models.
Is laptop size the screen or the whole laptop?
Laptop size is the screen only, measured diagonally from corner to corner. It does not include the frame or the body. For a bag, you need the body's width and depth instead, which the manufacturer lists separately in centimetres on the specification page.
How big is a 15.6-inch laptop in cm?
A 15.6-inch laptop has a screen diagonal of 39.6 cm. The body is narrower than that diagonal, but its exact width depends on the model, so check the manufacturer's specification page. For comparison, Apple's 15-inch MacBook Air is 34.04 cm wide and 23.76 cm deep.
Will a 15-inch laptop fit in a 14-inch bag?
Often not, so check the centimetres rather than the label. In our range, the Capri (33 cm wide) is listed for a 14-inch laptop. It takes a 14-inch MacBook Pro at 31.26 cm, but a 15-inch MacBook Air, at 34.04 cm, is about 1 cm wider than the bag.
Is an 11-inch laptop too small?
An 11-inch laptop is small for long days of work, because two windows side by side become cramped. It suits school, light travel and note-taking. If you mostly write documents and browse, a 13 or 14-inch screen gives more room while still fitting a compact bag.
The short version
If you only remember one thing: the laptop size is the screen, the bag size is the body. Find your laptop's width in centimetres, then choose a bag that is wider. For a 13-inch MacBook Air, the Torino works but is tight; for a 14-inch laptop, the Capri; for anything 15 to 16 inches, the Genova or the Firenze. Choosing a laptop by size and a bag by centimetres saves a return.