What Size Medicine Cabinet Do You Need Above the Sink

Key takeaways

• As a rule of thumb, choose a medicine cabinet that is about 70–90% of your sink or vanity width so it looks balanced and does not overwhelm the basin.
• Mount the cabinet so the mirror centre is roughly at average eye level (around 150 cm from the floor), with at least 30–35 cm clear above the tap spout to avoid door clashes.
• Standard cabinet depths of 10–15 cm work well above most sinks; go shallower in tight spaces to avoid bumping your head, or consider a recessed design.
• Stud positions, tiles and existing wiring may limit your maximum width and exact mounting height, especially for recessed models.
• If you only need secure storage rather than a wall mirror, a lockable box such as the Lockabox One medicine box can sit inside a cupboard instead of above the sink.

Why the size of your medicine cabinet matters

The size of your medicine cabinet affects far more than how many bottles and plasters you can fit inside. Above the sink, it becomes the main mirror for daily routines like shaving, brushing teeth and skincare. If it is too small, you spend your time leaning and adjusting to see properly. If it is too wide or tall, it can dominate the room and look visually heavy.

There is a practical side too. Doors that swing into taps, lights or nearby walls fast become annoying. A cabinet that hangs too low feels cramped over the basin, while one that is mounted too high can make it hard for children or shorter adults to use. Depth is just as important: a deep surface-mounted cabinet may offer loads of storage but leave you with a constant risk of bumping your head when you lean over the sink.

When you are working above an existing sink or vanity, you are also dealing with fixed points: plumbing, splashback tiles, wall studs and any lighting already in place. A cabinet that looks perfect in a catalogue might not work in your particular space. This is why starting with a tape measure and a few simple formulas is far more reliable than choosing by eye alone.

If you are wondering whether you would be better off with a different style altogether, it is worth understanding the main types of bathroom medicine cabinets before you commit to a size and installation style.

How wide should a medicine cabinet be over the sink?

Width is usually the first dimension people think about, and for good reason. It has the biggest impact on how the cabinet looks relative to your sink or vanity. There is one simple guiding principle: the cabinet should usually be a little narrower than the unit below it.

Rule of thumb for cabinet width vs sink or vanity

As a starting point, aim for a cabinet that is around 70–90% of the width of your sink or vanity top. This creates a balanced look with a small margin of wall visible at each side, and it helps keep the cabinet in proportion with the rest of the room.

• Single pedestal or small wall-hung sinks (40–55 cm wide): look for a narrow cabinet around 35–50 cm wide.
• Standard single-sink vanities (60–90 cm wide): a cabinet between 50–80 cm wide tends to look and feel right.
• Wider single-sink or small double vanities (90–120 cm): you can go up to 90–100 cm wide, or use two narrower cabinets above each basin.

The cabinet should not usually be wider than the vanity top, as this can look top-heavy and awkward. In compact bathrooms, keeping the cabinet closer to the 70% side of that range can help the space feel less cramped.

A simple measurement formula

To make things even easier, you can use a quick formula:

Recommended cabinet width = Vanity width × 0.75 to 0.85

So for a standard 80 cm wide vanity, a medicine cabinet between 60 and 68 cm wide will usually look well proportioned. For a 60 cm vanity, something in the 45–50 cm range is often ideal.

If you have wall lights either side of the mirror, remember to allow space for them. Measure from light fitting to light fitting and reduce your target cabinet width by at least 4–5 cm to keep a small gap either side.

Width and door swing clearances

Cabinet width also interacts with where the doors will swing. On a narrow wall where one side is close to a corner or shower screen, an over-wide cabinet can mean the door cannot open fully. If your basin is close to a side wall, consider:

• A single-door cabinet that opens away from the wall.
• Double doors where each leaf is narrower and needs less swing space.
• A recessed cabinet to gain a few extra centimetres.

To double-check clearances, tape out the planned cabinet width on the wall and roughly mark the door edges. Imagine the doors opening; make sure they will not hit taps, lights or nearby walls.

How tall should a medicine cabinet be above the sink?

Height is about both function and comfort. You want a mirror that works for as many people in the household as possible without feeling squeezed against the tap or ceiling. Most medicine cabinets fall somewhere between 50 and 90 cm tall.

Where to hang the cabinet: mirror height formula

The simplest way to set the height is to think in terms of eye level rather than exact numbers. You want the centre of the mirror portion to sit close to the eye level of the average user in the home, while still being usable for shorter adults and children.

• Typical mirror centre height: around 145–155 cm from the finished floor.
• Practical range for households with children: around 140–150 cm to keep more of the mirror usable for everyone.

You can work backwards from this. Measure the full height of the cabinet, then subtract half of that from your target centre height. The result is the recommended distance from the floor to the bottom of the cabinet.

For example, if your cabinet is 70 cm tall and you want the mirror centre at 150 cm:

• Half of 70 cm is 35 cm.
• 150 cm – 35 cm = 115 cm.
• Mount the bottom of the cabinet at about 115 cm from the floor.

Allowing for taps and splashback

Your tap and splashback create a minimum starting height. You need enough clearance between the top of the tap and the bottom of the cabinet so that the doors can open and you can comfortably use the mixer without hitting your hands or knuckles.

• Minimum clearance above tap spout: around 25–30 cm.
• More comfortable clearance: 30–35 cm, especially with taller mixer taps.

Measure from the tap spout or highest point of the mixer to where you intend the cabinet to start. If you have a tiled splashback, you can choose to align the base of the cabinet with the top of the tiles for a clean line. Just ensure you still have enough space for the mirror to sit at a comfortable viewing height.

Tip: If you have tall household members and a low ceiling, favour a slightly shorter cabinet hung higher rather than a tall one crammed too close to the tap. It is easier to add extra storage elsewhere than to live with an awkwardly low mirror.

How deep should a medicine cabinet be?

Depth is where a lot of people run into problems, particularly in small bathrooms. While deeper cabinets offer more storage, they also project further over the basin, bringing the mirror closer to your face and increasing the chance of bumping your head as you lean over the sink.

Standard depths and when they work

Most wall-mounted medicine cabinets fall within a fairly narrow depth range:

• Shallow cabinets: 8–10 cm deep – good for very small bathrooms or narrow walkways.
• Standard cabinets: 10–15 cm deep – suitable for most sinks and vanity setups.
• Extra-deep cabinets: 15–18 cm or more – best above deeper vanity tops, not pedestal basins.

A standard 10–15 cm depth works well with most vanity tops that are 45 cm or deeper. The projection feels natural and you can comfortably lean over the basin without your head hitting the cabinet as you move. Over a shallow wall-hung or pedestal sink, go towards the shallower end of the range.

Recessed vs surface-mounted depth

Recessed medicine cabinets sit partly inside the wall cavity, so they project less into the room. If you are worried about headroom, this can be a very effective way to reduce the apparent depth while keeping usable shelf space. For example, a 12 cm deep cabinet recessed by 7 cm only sticks out around 5 cm from the wall.

If your walls allow it, a recessed design can be especially helpful over compact basins or in narrow en-suites. You can learn more about the trade-offs in a dedicated comparison of recessed versus surface-mount medicine cabinets.

Quick reference: cabinet size ideas for common sink widths

Below are simple guidelines you can use as a starting point. Always cross-check them against your actual wall, tap height and any lights or tiles.

Small sinks (around 40–55 cm wide)

• Suggested cabinet width: 35–50 cm.
• Typical cabinet height: 50–70 cm.
• Depth: 8–12 cm, or recessed to keep headroom.

These setups benefit from compact, often single-door cabinets that keep things light and airy.

Standard single vanities (around 60–80 cm wide)

• Suggested cabinet width: 50–70 cm.
• Typical cabinet height: 60–80 cm.
• Depth: 10–15 cm depending on vanity top depth.

This is the most forgiving range; many off-the-shelf cabinets will work here without extensive adjustments.

Wider vanities and double sinks (around 90–120 cm+)

• Single large cabinet width: 70–100 cm, centred on the main basin.
• Two cabinet option: 45–60 cm wide over each basin for double sinks.
• Height and depth: similar to standard vanities, adjusted for ceiling and user height.

For larger vanities, visual balance becomes particularly important. A long countertop with a tiny cabinet above one basin can look odd; either choose a generous central cabinet or pair two smaller ones where the wall allows.

How studs, tiles and obstacles affect cabinet size

Even when you know your ideal cabinet dimensions, the wall itself can limit what you can actually install. Stud positions, tiles, wiring and existing fixtures all play a part, especially for recessed cabinets.

Stud spacing and recessed cabinets

In many homes, wall studs are spaced at regular intervals (often around 40 or 60 cm centre-to-centre). A recessed medicine cabinet usually needs to sit between studs, or you will have to alter the framing. That means your maximum cabinet width may be locked to the space between two studs unless you are willing to carry out more involved carpentry work.

Before choosing a wide recessed cabinet, locate the studs using a stud finder and mark their positions on the wall. Measure the clear distance between them; that measurement is your realistic maximum recess width. If it is smaller than the cabinet you had in mind, consider:

• A narrower recessed cabinet.
• A surface-mounted cabinet of your preferred width.
• Two narrower recessed units if the wall layout allows.

Tiles, wiring and existing lights

Tiles around the sink can be both a visual guide and a constraint. Many people like the bottom of the cabinet to line up with the top of the tiled splashback. This can lock in your mounting height and, for taller cabinets, may bring the top uncomfortably close to the ceiling. Prioritise function over perfect alignment if you have to choose.

Wiring for shaver sockets or over-mirror lighting can also limit your options. A cabinet that is too tall may overlap the light fitting, while one that is too wide could block a wall switch. Always map out any hidden wiring if you are cutting into the wall for a recessed installation.

Insight: When wall constraints make your ideal cabinet size impossible, it is usually better to choose a slightly smaller model with good positioning than to force a larger one into a compromised spot.

Should the medicine cabinet be narrower than the vanity?

In most bathrooms, yes: the medicine cabinet looks best when it is slightly narrower than the vanity or sink unit. This leaves a margin of wall on each side, making the arrangement feel intentionally framed rather than crowded. It also helps avoid situations where the cabinet edges sit dangerously close to side walls or adjacent fixtures.

There are a few exceptions. In very small cloakrooms where the sink is extremely narrow, you might choose a cabinet that is the same width as the basin for more mirror area. In wider family bathrooms, two matching cabinets above a long vanity can provide both symmetry and storage. But as a guiding principle, aim for a cabinet that is clearly centred over the basin and contained within the vanity width.

How far above the sink should the medicine cabinet be?

The gap between the sink and the bottom of the cabinet must accommodate your tap and still feel comfortable to use. Start by measuring from the finished floor to the top of your sink or worktop, and from the worktop to the top of the tap or mixer.

• Minimum gap from tap to cabinet base: around 25 cm so you can use the tap freely.
• Better everyday clearance: 30–35 cm, especially for taller or pull-out taps.
• Total height from floor to cabinet base: often lands around 110–125 cm once everything is balanced.

Check that this still gives you a comfortable mirror centre height using the earlier formula. If the tap is unusually tall, you may need to accept a slightly higher mirror, or choose a shorter cabinet to avoid clashing with ceiling or lights.

Headroom and everyday comfort

Beyond the exact measurements, think about how you actually move around the sink. Do you lean forward to splash your face? Do children stand on a stool to brush their teeth? Does someone shave daily in that mirror? These habits can reveal whether a particular depth or height will be comfortable in daily use.

As a rough test, stand at your sink and imagine the front of the cabinet sitting 10–15 cm forward of the wall. Lean forward as you normally would to wash your face or rinse. If your head would hit where the cabinet is, you either need a shallower or recessed model, or to hang it slightly higher (as long as the mirror remains usable).

When a wall medicine cabinet is not ideal

Sometimes the best size for your bathroom is no cabinet at all above the sink. If your wall is full of pipework, very narrow, heavily tiled or has low sloping ceilings, a traditional wall-mounted cabinet might be more trouble than it is worth. In those cases, you can separate storage from the mirror.

One option is to use a simple mirror above the sink and keep medication in a secure box stored inside a nearby cupboard or drawer. A compact lockable container such as the Lockabox One medicine box can help keep tablets out of reach of children without needing a wall-mounted cabinet.

If you need to carry medication between rooms or even outside the home, a portable organiser such as the three-layer medicine storage box with handle can be useful, particularly where a shared bathroom offers limited privacy or wall space.

For those who want a secure wall-mounted option elsewhere in the home, a dedicated lockable cabinet such as the Uniclife wall-mount medicine cabinet can sit in a hallway or utility room instead of directly above the bathroom sink.

Putting all the measurements together

Once you have your sink and wall measurements, it can help to sketch the layout or use painter’s tape to mark your proposed cabinet outline on the wall. Follow this order:

1. Measure the width of your sink or vanity.
2. Use 70–90% of that width to find your target cabinet width.
3. Check stud spacing and obstructions to confirm the maximum usable width.
4. Measure from the floor to the top of your sink or worktop, and from worktop to tap height.
5. Choose a cabinet height that allows at least 25–30 cm from tap to cabinet base and positions the mirror centre near eye level.
6. Decide on a depth that suits your basin type and available headroom, considering recessed options if needed.
7. Mark all of this on the wall, open and close imaginary doors, and adjust by a few centimetres if necessary.

By checking each dimension in turn, you are far less likely to end up with a cabinet that looks good on paper but feels awkward in daily use.