Floor vents are sized by the duct opening in the floor, width first, then length. The most common sizes are 4" x 10" and 4" x 12". Of the 1,725 LVP and LVT vents we built from October 2024 to October 2026, 44% were 4" x 10" and 37% were 4" x 12". Measure your own opening before you order.
Floor vent size chart
These are the duct-opening sizes we build VENT2MATCH® vents in, with each size's share of our LVP and LVT orders and the current price for a vent made from your flooring.
- 4" x 10"44.2% of orders$135 for an LVP or LVT vent
- 4" x 12"36.9% of orders$135 for an LVP or LVT vent
- 4" x 14"8.3% of orders$175 for an LVP or LVT vent
- 6" x 12"3.2% of orders$190 for an LVP or LVT vent
- 2" x 10"1.9% of orders$135 for an LVP or LVT vent
- 2" x 12"1.9% of orders$135 for an LVP or LVT vent
- 6" x 10"1.2% of orders$185 for an LVP or LVT vent
- 2" x 14"1.2% of orders$135 for an LVP or LVT vent
- 6" x 14"1.2% of orders$190 for an LVP or LVT vent
Share of 1,725 LVP and LVT vent units ordered from Vents.com, October 2024 to October 2026. Prices as listed in October 2026.
Two sizes cover most homes. 4" x 10" and 4" x 12" together made up 81% of what we built. When a house has more than one size, it is usually a mix of those two, with a 4" x 14" or a 2"-wide vent where the duct had to fit between joists or near a wall.
Older homes, additions and custom HVAC work can have openings that don't match a standard size. If yours isn't on the chart, check the measuring guide and send us your measurements before ordering.
How to measure a floor vent
Measure the hole in the floor, not the old register. The metal cover is larger than the duct opening underneath it. A 4" x 10" opening often has a register top around 5.5" x 11.5", so measuring the cover gets you the wrong size.
- Remove the existing registerLift it straight out. Most drop-in registers sit loose in the opening.
- Measure the opening widthMeasure the inside of the metal duct from edge to edge across the short side.
- Measure the opening lengthMeasure the long side the same way.
- Write it as width x lengthA 4-inch by 10-inch opening is a 4" x 10" vent.
- Check your flooring thicknessWe build vents from flooring at least 5 mm thick. The thickness is on the box or the spec sheet. That's the plank itself, not counting any attached pad.
- Note the plank directionWrite down or photograph which way the planks run at each vent so the vent's pattern lines up with the floor.
- Measure every ventDon't assume every opening in the house is the same size.
For thickness, floor height changes and vents near walls or cabinets, see our full guide on how to measure floor vents.
Should you round up?
Order the size that matches your duct opening. Our flush vents are built slightly larger than the standard opening, so the metal-reinforced frame rests on the subfloor around the hole. The installation guide calls for at least ¼ inch of overlap on every side, and it doesn't need to be even all the way around.
Sizes for LVP, LVT and engineered hardwood
The duct opening sets the size, whatever the flooring. The flooring type changes what to check:
- LVP (luxury vinyl plank)5 mm minimumMeasure the plank itself, not counting any attached pad, and note plank direction.
- LVT (luxury vinyl tile)5 mm minimumNote the pattern direction on stone and tile looks.
- Engineered hardwood5 mm minimum, 4" wide minimumPlanks need to be at least 4 inches wide. Check total thickness and grain direction. Set aside boards without bows or damage. See hardwood floor vents, and how flush hardwood vents install.
Keep a few spare planks or tiles from your installation. Your vent is built from your own flooring, so it matches the color, texture and dye lot of the floor around it. If your floor is vinyl, see how LVP vent covers made from your own plank compare with standard metal registers.
When to measure and order
The best time is after you've chosen your flooring and before installation starts. Your installer can use the vent frame as a template and cut the surrounding planks before they lock into the floor. If your floor is already down, you can still measure and order; the opening just gets cut into the finished floor, which takes more care. Read why to order custom vents before installing new flooring.
Floor register vs. cold air return sizes
Supply registers blow conditioned air into the room. They are the smaller vents, usually 2", 4" or 6" wide. Cold air returns pull air back to the furnace and are much larger. We build matching egg-crate returns in 6" and 8" widths from 20" to 36" long.
Our most-ordered return sizes are 8" x 24", 8" x 30" and 8" x 20". Returns are a smaller product line (about 28 units in the same two years), so we list the order rank rather than percentages. Measure a return the same way: remove the grille and measure the opening. See matching cold air return covers.
Order a vent in your size
Frequently asked questions
What is the most common floor vent size?
4" x 10". It was 44% of the 1,725 LVP and LVT vents we built from October 2024 to October 2026. 4" x 12" was second at 37%.
Do I measure the vent cover or the hole?
Measure the hole. Remove the register and measure the inside of the duct opening. The cover is larger than the opening; a 4" x 10" opening often has a cover around 5.5" x 11.5".
Is a 4x10 vent 4 inches by 10 inches?
Yes. The size describes the duct opening: 4 inches wide by 10 inches long. The register that covers it is larger.
Are floor vent sizes standard?
Most homes use a handful of standard opening sizes, mainly 2", 4" and 6" widths in 10", 12" and 14" lengths. Older homes, additions and custom ductwork can differ, so measure each opening.
What size is a cold air return?
Returns are larger than supply registers. Our most-ordered return sizes are 8" x 24", 8" x 30" and 8" x 20". We build 6" and 8" widths from 20" to 36" long.
How thick does my flooring need to be for a custom vent?
At least 5 mm. That applies to LVP, LVT and engineered hardwood. Hardwood planks also need to be at least 4 inches wide.
Can I use the same size vent if I'm changing flooring?
Usually, yes. The duct opening doesn't change when you replace the floor. The finished floor height might, so check how the new flooring and underlayment change the height around the vent.
Find your floor brand. We build vents from most major vinyl plank and engineered hardwood lines. Look up yours on our LVP brands or hardwood brands page. Brands our customers order most often include COREtec, Mohawk SolidTech, Provenza, Flooret, Home Decorators Collection and Cali Vinyl Pro.
Related guides
- How to remove a floor vent coverLift out an old register without scratching the floor, then measure the opening.
- What custom floor vents costPrices by size for LVP vents and returns, and what drives the cost.
- Matching cold air return coversEgg-crate returns made from your LVP, LVT or hardwood, in all 8 sizes.
- When to order vents before your installWhen to measure, set a plank aside and order so vents arrive on time.