What size bag for which MacBook?
This is the most common question asked before buying a MacBook bag or sleeve, and the one that causes the most
returns. A "13-inch" doesn't always fit into a "13-inch" bag, and a
14-inch MacBook Pro sometimes fits into a compartment advertised for 13 inches. Here's how to avoid
making a mistake.
Why inches are not enough
The inch measurement refers to the screen's diagonal, not the computer's overall size.
Two models advertised at different sizes can have almost identical chassis,
because the thinness of screen bezels has evolved significantly between
generations.
Practical consequence: a recent 14-inch MacBook Pro is barely larger than a
13-inch MacBook Air. Conversely, an older 15-inch MacBook Pro is bulkier
than a current 15-inch Air.
The only reliable measurement is therefore the actual measurement: width, depth, thickness, in
centimeters.Model Width Depth Thickness

Dimensions of current MacBooks
MacBook Air 13” ≈ 30.4 cm ≈ 21.5 cm ≈ 1.1 cm
MacBook Pro 14” ≈ 31.3 cm ≈ 22.1 cm ≈ 1.5 cm
MacBook Air 15” ≈ 34.0 cm ≈ 23.8 cm ≈ 1.2 cm
MacBook Pro 16” ≈ 35.6 cm ≈ 24.8 cm ≈ 1.7 cm
Indicative values for recent generations. Always check the technical specifications of
your exact model on the manufacturer's website: dimensions vary by year.
This table shows the essential: between an Air 13 and a Pro 14, the difference is less than one
centimeter in width. Between a Pro 14 and an Air 15, it exceeds two and a half centimeters.
The three-centimeter rule
For a bag, the correct internal dimension is calculated as follows:
Computer width + 2 to 3 cm. Below this, insertion becomes difficult and the leather
gets stressed with each use. Above 4 cm, the computer floats, slides, and bumps against the
closures.
This margin must include protection: a microfiber-lined or padded bag
takes up a few millimeters on each side. A bag that states its internal dimensions
is more reliable than one that states its external dimensions.
The three most common mistakes
Buying by diagonal measurement. "I have a 14-inch, I'll buy a 14-inch sleeve": without the
centimeters, you're buying blind.
Forgetting accessories. The MacBook fits, but the charger, mouse, cables, and
headphones have no space. They end up at the bottom, against the aluminum — and scratch it. If you
carry a complete ecosystem, the question is no longer the size of the computer but
internal organization.
Buying too large "just in case". An oversized bag allows the computer to
move with every step. Stability is part of protection.
Too big or too small: what are the risks?
A bag that's too small stresses the seams and closures with each insertion: the bag
gets damaged. A bag that's too big allows the device to move: the computer
gets damaged, with marked corners, screen under pressure, micro-scratches on the lid.
The right fit is recognized by a simple sign: the computer slides in effortlessly, but does not
move when you shake the closed bag.
What if I change MacBooks?
This is a real consideration when buying an item meant to last. A computer is replaced
every four to six years; a full-grain leather bag lasts for decades.
Two strategies: choose a bag sized for the category you will keep
(13-14 inches, or 15-16 inches), rather than for a specific model; the differences within
the same category remain small from one generation to the next. Or accept that the item
is tailored exactly for one model, knowingly, if the precision of
the fit matters more than versatility.
The Hervain Case

Le Hervain is designed for the 13-inch MacBook Air, with a main compartment
lined with smooth microfiber and dedicated storage for the charger, Magic Mouse,
AirPods Pro, keyboard, and cables.
Its external dimensions: L 43 × H 28.5 × D 5 cm.
This choice is deliberate: rather than a large empty compartment that "fits everything," each
slot has been developed to the millimeter for a specific item. This allows you to set up
and store everything in seconds, without anything moving or getting scratched.
If you are unsure about your model's compatibility, please contact us: we will provide you with
the exact internal dimensions and respond within 24 business hours.