The 2024 Mac mini (M4 and M4 Pro) is a different shape from the 2010–2023 models. The old mini was a wide, flat 197 mm square, about 36 mm tall, which fit neatly in 1U. The new one is 127 × 127 mm and 50 mm tall: a smaller footprint but taller, and that one change decides how you rack it. Mac minis are popular as build servers, CI runners, media servers and small AI inference boxes. Here's how to choose a rack mount for the new one.

The numbers that matter

Size: 127 × 127 × 50 mm (W × D × H), the same for the M4 and the M4 Pro.
1U opening: 44.45 mm. The M4 mini is 5.5 mm taller, so it needs 2U.
Power: internal supply with a standard power cord. There's no brick to hide.
Ports: two USB-C ports and a headphone jack on the front. On the back: Thunderbolt (three ports), HDMI, Ethernet and power.
Power button: on the underside, near the rear corner. This matters more than you'd think in a rack.

Why 2U and not 1U

A 50 mm box doesn't fit in a 44.45 mm space, whatever the listing says. Mounts sold as "1U" for the M4 either let the mini stand proud of the rack unit or turn it on its side. On its side, the footprint becomes 50 mm wide by 127 mm tall, which is 3U of height, and you lose the stable base. A 2U mount keeps the mini upright, with room for an open floor underneath so it can draw air, which leads to the next point.

Airflow: it breathes from the bottom

The M4 Mac mini draws air in through the vent around its base and pushes it out through the back. A mount with a solid shelf right under the base starves it. When you compare mounts, check that the floor under the mini is open or vented and that the back is clear. Don't let a cable bundle sit against the rear vent.

For a warm closet or an enclosed rack, PETG is fine at normal room temperatures, and ASA handles more heat. Our materials page compares the two.

The power button problem

The power button is underneath the mini, so once it's in a mount you may not be able to reach it. Plan for that:

In macOS System Settings → Energy, turn on Start up automatically after a power failure. A switched PDU outlet or smart plug then works as your power button.
Turn on wake for network access if you manage the mini remotely.
If you want to reach the button, choose a mount that leaves the rear corner open underneath, or pull the mini forward when you need it.

10-inch rack: one Mac mini

A 10-inch rack has roughly 220 mm of usable width between the rails. One M4 mini (127 mm) fits with room for cable routing beside it. Two side by side would need 254 mm before any wall between them, so they won't fit. For two minis in a 10-inch rack, stack two 2U mounts.

Our 10" 2U Mac mini (M4) rack mount is $59.99, prints in one piece, and ships in 2–3 business days. If you still run an older 2010–2023 mini, it's 1U: see the 10" 1U Mac mini (2010–2023) mount.

19-inch rack: one, two or three

Two side by side (the sweet spot)

In a 19-inch rack, two M4 minis fit side by side in 2U with plenty of room between them. Our 19" 2U dual Mac mini (M4) mount is $69.99. It prints as two halves joined by a tongue-and-groove seam and three M4 bolts across the centre spine, with the nuts held in printed pockets, so it assembles with one hex key.

One in a 19-inch rack

For a single mini in a 19-inch rack, use the rack-mount generator: pick 19-inch, choose the Mac mini or enter 127 × 50 × 127 mm, set one device, and you'll have a design and a price in about 30 seconds. Our 19" 2U mounts start from $54.99.

Three or more

Three M4 minis also fit across a 19-inch rack in 2U. Metal options exist: Sonnet's RackMac mini for M4 holds three in 2U and lists around $300–350. With the generator you can set two devices per mount, and for three or more, two mounts side by side in adjacent spaces work too. Or send us the layout you want through the custom quote page.

Printed vs metal for a Mac mini

Metal Mac mini kits are well made and rigid. They also cost from about $99 for older-mini 1U kits to $300+ for multi-unit M4 enclosures, and stock can be patchy. A printed mount weighs less, costs less, and can be sized to your exact layout. Its limits: it's plastic, so keep PETG away from real heat sources, and treat it as a holder for 0.7 kg computers, not a shelf for heavy gear.

Buying checklist

Is it actually 2U for the M4? 1U listings won't fit an upright M4 mini.
Is the floor under the mini open or vented?
Is the rear clear for the Thunderbolt and power cables, with nothing pressed against the exhaust?
Can you reach the front USB-C ports, or do you not care?
Does the seller have a fit guarantee? Ours: send a photo within 30 days and we reprint free (terms).

Racking other small machines too? See “Lenovo ThinkCentre Tiny vs Dell OptiPlex Micro” and our “10-inch rack starter guide”. The full catalog is on the rack mounts page.

FAQ

Does a Mac mini M4 fit in 1U?

Not upright. It's 50 mm tall and 1U is 44.45 mm. Use a 2U mount.

Will the M4 mount fit the M4 Pro?

Both share the 127 × 127 × 50 mm case, so a mount sized for one fits the other. The M4 Pro has Thunderbolt 5 ports on the back instead of Thunderbolt 4, but they're in the same places.

Can I fit two M4 minis in a 10-inch rack?

Not side by side: two need 254 mm and a 10-inch rack offers roughly 220 mm. Stack two single 2U mounts instead.

Mac mini M4 rack mount options: 10-inch vs 19-inch, one or two