What is the standard trash can size for under a sink?

There is no single standard, but 30 liters (8 gallons) is the most common for a 36-inch-wide base cabinet. The actual fit depends on your cabinet depth and the position of the P-trap, so measure before buying.

How do I measure the height for an under-sink trash can?

Measure from the cabinet floor to the lowest point of the P-trap. That is your true height limit. If the can has a lid, measure with the lid closed and with it open to make sure it clears the sink basin above.

Can a 13-gallon trash can fit under a sink?

Sometimes, but only if the cabinet is at least 24 inches wide and the trap is positioned low and to the back. A 13-gallon can is about 12 by 12 inches at the base and 22 inches tall, which leaves little clearance. Measure your space; many people end up with an 8-gallon can instead.

Should I get a pull-out trash can or a freestanding one?

A pull-out can is easier to access and uses the full depth of the cabinet, but it needs a sturdy slide and a clear track. A freestanding can is simpler and cheaper, but you must lift it out to empty it, which requires headroom above the rim. Choose based on your cabinet's depth and your lifting comfort.

Trash Can Dimensions for Under-Sink Fit: A Stage-by-Stage Measurement Guide

Stage 1: Measure the Cabinet Interior, Not the Door

Start with the empty cabinet. Remove everything from under the sink so you can see the full interior. Use a metal tape measure, not a cloth one, because cloth can sag and give you a reading that is an inch or more off.

Measure three dimensions: depth (front to back), width (left to right), and height (floor to the underside of the countertop). Record each in inches. Do this twice to catch errors. The depth matters most for a pull-out can; the height matters most for a swing-top or step can.

Do not measure the door opening and assume it matches the interior. Doors are often narrower than the cabinet box. Also check the cabinet floor: if it has a lip or a raised edge at the front, your trash can must sit inside that lip, which reduces usable depth.

The average kitchen trash size under a sink is usually 30 to 50 liters (8 to 13 gallons), but the cabinet dimensions vary widely. A 13-gallon can needs roughly 12 by 12 inches of floor space and about 22 inches of height. Measure your space first, then compare with product specs.

Ignore the door swing for now. You will check that in Stage 3. For the moment, you only need the raw interior box dimensions.

Depth: front edge of the cabinet floor to the back wall
Width: left interior wall to right interior wall
Height: floor to the underside of the countertop
Note any pipes, braces, or raised floor lips
Measure twice and write down all numbers

Measurement	Where to place the tape	Why it matters
Depth	Front edge of floor to back wall	Determines if a pull-out slide fits
Width	Interior wall to interior wall	Sets maximum can width, leaving room for the door hinge
Height	Floor to countertop underside	Limits can height, especially with a lid or step pedal
Obstructions	Around the P-trap and supply lines	Narrowest point; often reduces usable depth by 2-4 inches

Stage 2: Map the Obstructions (P-Trap, Supply Lines, Garbage Disposal)

The under-sink area is never an empty box. The P-trap and the two water supply lines usually take up the back third of the cabinet. A garbage disposal adds a large cylinder that extends down and to one side, which can eat into your usable width and height.

Use a flashlight to find the lowest point of the P-trap. Measure the vertical distance from the cabinet floor to the bottom of the trap. This is your true height limit for a can that slides under the trap. For a can that sits beside the trap, measure the width of the clear floor space on each side of the drain pipe.

Trace the path of the supply lines. They often come up from the floor or out from the wall at the back. A trash can that fits in the front half of the cabinet may clear these lines, but a can that slides all the way back might hit them. Mark the deepest point where the can can sit without touching any pipe.

If you have a garbage disposal, measure its diameter and the distance from the cabinet wall to the disposal's outer edge. A 4-inch clearance between the can and the disposal is the minimum for easy removal. The disposal also adds weight, so a freestanding can is safer than a hanging one in that cabinet.

For a quick visual check, cut a piece of cardboard to the can's planned base dimensions and slide it into the cabinet. This cardboard template will show you immediately whether the can clears the pipes before you buy anything.

Open kitchen cabinet showing the P-trap and supply lines under the sink

Stage 3: Choose the Can Shape and Size Category

Once you know the clear space, decide between a freestanding can, a pull-out slide, or a hanging can. A freestanding can is the simplest: you lift it out to empty it, so it needs a few inches of clearance above for lifting. A pull-out slide mounts to the cabinet floor or wall and glides forward, so it only needs to fit inside the box when closed.

Hanging cans attach to the inside of the cabinet door or the side wall. They free up floor space but have a smaller capacity, usually 10 to 20 liters (2.5 to 5 gallons). They also require the door to be strong enough to hold the weight, and the can must clear the P-trap when the door swings open.

For most under-sink cabinets, the practical range is 20 to 40 liters (5 to 10 gallons). A 30-liter (8-gallon) can is a common choice because it fits in a standard 36-inch-wide base cabinet without crowding. A 40-liter (10.5-gallon) can needs a wider cabinet and a careful check of the height under the trap.

The table below summarizes common can sizes and typical cabinet requirements. These are starting points, not rules, because the exact fit depends on your cabinet depth and the position of the trap.

If your cabinet is deeper than 24 inches, you can fit a wider can, but you still have to work around the trap. A shallow can that is tall and narrow often fits better than a wide, short one because the trap takes up the center.

Capacity (liters)	Capacity (gallons)	Typical base dimensions (inches)	Minimum cabinet width (inches)	Notes
10-20	2.5-5	10-12 wide, 10-14 deep	15	Good for hanging cans or small kitchens
20-30	5-8	12-14 wide, 14-18 deep	18	Fits most 36-inch base cabinets
30-40	8-10.5	14-16 wide, 16-20 deep	21	Needs deep cabinet and low trap
40-50	10.5-13	16-18 wide, 18-22 deep	24	Rare under sink; usually in a pantry

Pull-out trash can slide mounted inside an open kitchen cabinet

Stage 4: Verify Clearance for the Door, Lid, and Removal

A can that fits inside the box can still fail if the door does not close. Hinges take up space on the sides, so the usable width is often 1 to 2 inches less than the interior width. Close the door with the can in place to confirm the hinges do not pinch the can's sides.

The lid adds height. A step pedal adds height at the front. Measure the can's total height with the lid closed and with the lid open if it swings back. The open lid must clear the underside of the countertop and the sink basin, which can drop down several inches below the countertop surface.

For removal, the can needs a few inches of vertical clearance above the top rim so you can lift it straight out. If the space above is tight, choose a can with a removable liner or a bag that you can lift out without pulling the whole can. A can that fits snugly against the countertop underside will be a daily frustration.

Test the removal motion before you commit. Stand in front of the open cabinet, grab the can's handles, and lift. If you have to tilt it to get it past the sink drain, you will spill. A can that is 2 inches shorter than the cabinet height is usually easier to handle than one that just fits.

Finally, check the floor. If the cabinet has a toe kick, the floor inside is level. If not, the can may rock. A non-slip mat or small shims can fix this, but it is easier to know before you buy.

Close the door with the can inside to check hinge clearance
Measure the can's height with the lid closed and open
Check the sink basin overhang above the can
Lift the can to confirm you can clear the top rim
Look for a toe kick or uneven floor that causes rocking

Stage 5: Compare Product Specs and Plan for Returns

When you shop, read the product listing's 'product dimensions' line, not just the capacity. A 13-gallon can from one brand can be 2 inches wider than another brand's 13-gallon can. Write down the can's width, depth, height, and weight, and compare them to your cabinet measurements.

Bring your cabinet measurements with you. Keep a note in your phone with the interior width, depth, height, and the trap clearance. When you find a candidate, mentally add 1 inch of clearance on each side and 2 inches at the front for the door. If the numbers fit, you are likely safe.

Check the return policy before you buy. Under-sink trash cans are often sold in sealed boxes, and some retailers charge a restocking fee for opened items. Ask if you can test the fit at home. A few stores allow this, and it saves you from being stuck with a can that does not clear the trap.

If you are between two sizes, buy the smaller one. A slightly smaller can is easier to remove and leaves room for a recycling bin or cleaning supplies. A can that is too large will sit crooked against the pipes and may push the door open.

Finally, measure the bag size. A can that fits the cabinet but uses non-standard bags will cost you more over time. Most under-sink cans take 8- to 10-gallon bags, but check the listing. A bag that is too small will fall in; one that is too large will bunch up and may not close.