TL;DR: Most kitchens need a range hood between 300 and 900 CFM. For gas ranges, divide your total burner BTU output by 100 to get the minimum CFM (a 40,000 BTU range needs at least 400 CFM). For electric and induction cooktops, calculate 100 CFM per linear foot of cooktop width (a 30-inch cooktop needs 250 CFM minimum). Add 100-200 CFM for island installations. If your hood exceeds 400 CFM, you may need a make-up air system per local building code. When in doubt, size up — you can always run a powerful hood at lower speeds, but you can't add CFM after installation.
Range hoods are sized in cubic feet per minute, or CFM — the volume of air the hood can move out of your kitchen every minute. Get this number wrong and the hood either fails to capture smoke and grease or pulls so hard it triggers backdraft, noise complaints, or building code issues with make-up air.
This guide walks through the three CFM calculation methods, when each applies, what changes for island vs wall installations, and how to factor ductwork into the final number. By the end, you'll know exactly what CFM your kitchen needs and what to verify before ordering.
| Cooktop / Range Type | Recommended CFM |
|---|---|
| 30-inch electric or induction | 250-300 CFM |
| 36-inch electric or induction | 350-400 CFM |
| 48-inch electric or induction | 500-600 CFM |
| 30-inch gas range (30,000-40,000 BTU) | 300-400 CFM |
| 36-inch gas range (45,000-60,000 BTU) | 450-600 CFM |
| 48-inch pro-style gas (60,000-90,000 BTU) | 600-900 CFM |
| 60-inch pro-style gas (90,000-120,000 BTU) | 900-1,200 CFM |
| Island installations (any size) | Add 100-200 CFM to wall-mount baseline |
These are minimum recommendations under typical install conditions (hood mounted 30 inches above cooktop, ductwork under 10 feet with two or fewer 90° elbows). Add CFM for longer duct runs, higher mounting heights, or heavy-cooking households.
CFM stands for cubic feet per minute — the volume of air a range hood moves at maximum speed. A 600 CFM hood removes 600 cubic feet of air every minute it runs at full power; a 900 CFM hood removes 900 cubic feet per minute.
CFM ratings come from manufacturer testing under controlled conditions. Real-world performance is typically 60-80% of rated CFM once you account for:
This is why the rule of thumb is to size up rather than down. A 600 CFM hood running at 50% delivers cleaner ventilation than a 300 CFM hood running at 100%, and it does so more quietly.
For gas ranges, the standard rule from the Home Ventilating Institute (HVI) is:
1 CFM for every 100 BTUs of total burner output
Add up the BTU rating of every burner on your cooktop, then divide by 100.
Examples:
| Total Cooktop BTU | Required CFM |
|---|---|
| 30,000 BTU (4-burner standard gas) | 300 CFM |
| 40,000 BTU (4-burner mid-tier) | 400 CFM |
| 50,000 BTU (5-burner premium) | 500 CFM |
| 60,000 BTU (6-burner pro-style 36-inch) | 600 CFM |
| 90,000 BTU (6-burner pro-style 48-inch) | 900 CFM |
| 120,000 BTU (8-burner pro-style 60-inch) | 1,200 CFM |
For brand-specific burner BTU ratings, see our ZLINE Appliances Reviews, Forno Appliances Reviews, and ZLINE vs Thor Kitchen Appliances comparison — pro-style brands typically use 18,000+ BTU primary burners while mass-market brands use 9,000-12,000 BTU burners.
For electric and induction cooktops, BTU calculations don't apply — these surfaces don't burn fuel and produce less ambient heat. The HVI rule for electric/induction is:
100 CFM per linear foot of cooktop width
| Cooktop Width | Required CFM |
|---|---|
| 24 inches (2.0 ft) | 200 CFM |
| 30 inches (2.5 ft) | 250 CFM |
| 36 inches (3.0 ft) | 300 CFM |
| 48 inches (4.0 ft) | 400 CFM |
| 60 inches (5.0 ft) | 500 CFM |
Electric and induction cooktops still produce smoke and grease — they just produce less ambient heat than gas. The width-based calculation accounts for the area where smoke and steam rise. For dual-fuel ranges (gas cooktop, electric oven), use the gas BTU calculation since the cooktop is what determines hood sizing.
The Trade Table carries electric ranges, induction ranges, gas ranges, and dual fuel ranges across every standard width.
A third HVI calculation accounts for total kitchen size — important for open-concept layouts where smoke can spread before the hood captures it.
Your range hood should be capable of refreshing the kitchen air 15 times per hour
The math:
Example: A 12 × 14 ft kitchen with 9 ft ceilings = 1,512 cubic feet × 15 = 22,680 ÷ 60 = 378 CFM
For most enclosed kitchens, the cooktop-based calculation (Method 1 or 2) gives a higher number than the volume calculation. Always pick the larger CFM figure of the two methods to ensure adequate ventilation under both heavy-cooking and ambient conditions.
Where the hood mounts changes how much CFM you need.
Wall mount and under-cabinet hoods sit against a back wall, which channels rising smoke directly upward into the hood. Standard CFM calculations apply.
Island hoods hang from the ceiling above a center cooktop with no wall to direct smoke. Side drafts from open kitchens or HVAC systems can push smoke out from under the hood before it gets captured.
Add 100-200 CFM to the calculated minimum for island installations.
| Cooktop Size | Wall Mount CFM | Island Hood CFM |
|---|---|---|
| 30 inches | 300 CFM | 400-500 CFM |
| 36 inches | 400-500 CFM | 600-700 CFM |
| 48 inches | 600 CFM | 800-1,000 CFM |
| 60 inches | 900 CFM | 1,100-1,200 CFM |
Downdraft hoods (which pull smoke down through the cooktop instead of up) typically need 600+ CFM regardless of cooktop size because they fight against rising heat. Use them only when overhead ventilation isn't an option. For more on hood styles and mounting types, see our 9 types of range hoods guide.
Real-world airflow is reduced by ductwork resistance. Every additional foot of duct, every elbow, and every transition reduces the effective CFM your hood actually delivers.
Add CFM to compensate for:
Example: A kitchen requires 600 CFM by cooktop calculation. Ductwork is 18 feet long with three 90° elbows and a wall cap. Adjusted requirement: 600 + 8 (extra duct) + 50 (extra elbows) + 40 (cap) = 698 CFM minimum.
This is why pro installers recommend: shortest duct run possible, 6-inch round ducting, and minimum elbows. A poorly designed duct system can drop a 600 CFM hood to 400 CFM of effective airflow.
The higher your hood sits above the cooktop, the more CFM you need to capture smoke before it escapes sideways.
Recommended mounting heights:
| Hood Type | Minimum Height | Maximum Height |
|---|---|---|
| Under-cabinet | 24 inches | 30 inches |
| Wall mount | 24 inches | 36 inches |
| Island hood | 30 inches | 36 inches |
| Pro-style hood (over pro range) | 30 inches | 36 inches |
For every inch above the recommended minimum, plan to size up CFM by 5-10%. A hood at 36 inches needs roughly 30% more CFM than the same hood at 24 inches to deliver equivalent capture performance.
Tall ceilings and chimney extensions: Most range hoods ship with telescoping chimneys for 8-9 ft ceilings. Above 9 ft, you'll need an extension kit. The hood's effective working area still ends at the cooktop, so extending the chimney doesn't change CFM needs — but if you also raise the hood (some homeowners do this for aesthetic reasons in tall-ceiling kitchens), you're back to needing more CFM.
Range hoods over 400 CFM can create negative air pressure in your home — pulling air out faster than it naturally enters through windows, doors, and HVAC. This causes three problems:
To prevent these issues, most U.S. building codes (including the IRC) require a make-up air system for any range hood over 400 CFM. A make-up air system pulls fresh outside air into the home at a rate matching the hood's exhaust, neutralizing the pressure differential.
Make-up air systems typically cost $1,500-$4,000 installed, so this is a meaningful budget consideration when choosing between a 400 CFM and a 600 CFM hood. Check with your local building inspector before ordering — code thresholds vary by state and jurisdiction.
If make-up air infrastructure isn't feasible, a 400 CFM hood is the practical ceiling. For most non-pro-style residential cooking, 400 CFM is genuinely sufficient.
Ducted hoods exhaust air outside the home; ductless (recirculating) hoods filter air through carbon filters and return it to the kitchen.
Ducted hood CFM ratings reflect actual exhaust capacity — the number on the spec sheet is what reaches outside.
Ductless hood CFM ratings reflect motor capacity — but actual cleaning performance is much lower because the filter blocks airflow. A 400 CFM ductless hood typically delivers the equivalent of a 200-300 CFM ducted hood.
For heavy cooking, ducted is always better. Ductless makes sense only when ductwork isn't possible (condos, rental units, mid-floor apartments). For a complete breakdown, see our ducted vs ductless range hood comparison.
The Trade Table carries ductless range hoods configured for recirculating installs, plus wood range hoods and copper range hoods for design-focused remodels.
Hood size should match or slightly exceed cooktop width — never smaller. The standard sizing rule:
Range hood width = cooktop width, with 3 inches of overhang on each side ideal
For a 30-inch cooktop, a 30-inch hood is acceptable but a 36-inch hood captures smoke better. For a 36-inch cooktop, a 36-inch hood works but 42 inches is preferred. Pro-style installations almost always use a hood wider than the cooktop.
The Trade Table carries range hoods in standard widths to match every kitchen layout: 24, 30, 36, 42, 48, and 60 inches. Browse the full range hood collection to filter by size, mount type, and CFM rating.
For broader range and hood pairing decisions, see our guides on slide-in vs freestanding ranges and counter depth vs standard depth refrigerators — kitchen remodels rarely involve just one decision in isolation.
Range hoods at the same CFM rating don't all perform identically. Pro-style brands use larger blowers, better motor isolation, and tighter duct connections that translate to higher real-world airflow.
Premium tier ($1,500-$5,000+): Vent-A-Hood, Futuro Futuro, ILVE Range Hood. Italian and American craftsmanship with premium blowers that deliver 90%+ of rated CFM in real-world installs.
Mid-premium tier ($800-$2,500): ZLINE, Forno, Hauslane, Victory Range Hood. Pro-style aesthetics with reliable performance at attainable pricing.
Mid-tier ($300-$1,000): Cosmo, Thor Kitchen. Solid build quality with focus on standard CFM ratings and core feature sets.
For a power consumption breakdown of running a range hood and other kitchen appliances continuously, see our guide on how many watts a refrigerator uses — kitchen ventilation interacts with whole-home electrical planning more than buyers expect.
The right CFM depends on your cooktop type and size. For gas ranges, divide total burner BTU output by 100 (a 40,000 BTU range needs 400 CFM). For electric or induction cooktops, calculate 100 CFM per linear foot of width (a 30-inch cooktop needs 250 CFM). Add 100-200 CFM for island installations. Most kitchens need 300-900 CFM total.
CFM stands for cubic feet per minute — the volume of air the range hood moves at maximum speed. A 400 CFM hood removes 400 cubic feet of air per minute. Higher CFM means more powerful ventilation, but also more noise and potential need for make-up air systems.
Yes, for most residential kitchens. A 400 CFM hood handles 30-inch electric or induction cooktops, 30-36 inch gas ranges with standard burner output (under 40,000 BTU total), and light to moderate cooking loads. Pro-style gas ranges with 60,000+ BTU output need 600+ CFM to keep up with the heat.
Yes, for most kitchens with mid-to-high-end cooking demands. 600 CFM handles 36-inch gas ranges, 48-inch electric or induction cooktops, and most island installations of standard ranges. Pro-style 48-inch+ gas ranges may need 900-1,200 CFM. Note that 600 CFM exceeds the 400 CFM threshold for make-up air requirements in most jurisdictions.
For small kitchens with electric or induction cooktops 30 inches or smaller, yes. For gas ranges or any cooktop with high-heat cooking (frying, wok cooking, searing), 300 CFM is the bare minimum and you'll likely want to size up. Many ductless hoods are rated at 300 CFM but deliver effective airflow closer to 150-200 CFM after filter resistance.
Most 36-inch gas ranges have 45,000-60,000 BTUs of total burner output, requiring 450-600 CFM. Pro-style 36-inch gas ranges with 18,000+ BTU primary burners and 6 burners total can exceed 70,000 BTU — needing 700+ CFM. Always check the manufacturer's spec sheet for total cooktop BTU before sizing the hood.
48-inch ranges vary widely by configuration. A 48-inch gas range with 6 burners and a griddle typically produces 75,000-90,000 BTU, requiring 750-900 CFM. A 48-inch electric induction range needs 400-500 CFM (4 ft × 100 + buffer). 48-inch dual fuel ranges follow the gas calculation since the cooktop is gas. For all 48-inch installations, plan for make-up air infrastructure.
Yes. Island hoods don't have a back wall to channel rising smoke, so cross-drafts from open kitchens, HVAC, and foot traffic can disrupt capture. Add 100-200 CFM to the wall-mount baseline calculation for island installations. A cooktop that needs 400 CFM as a wall installation typically needs 500-600 CFM as an island installation.
Three potential issues: (1) excessive noise, especially on higher fan speeds; (2) make-up air requirements once you exceed 400 CFM, which add $1,500-$4,000 to install costs; and (3) potential back-drafting of gas appliance flues if make-up air isn't installed, which is a carbon monoxide safety concern. Higher CFM isn't always better — match the hood to actual cooking demands.
Make-up air is fresh outside air supplied to your home at a rate matching what your range hood exhausts. Most U.S. building codes require make-up air for range hoods over 400 CFM to prevent negative air pressure, back-drafting of gas appliances, and HVAC strain. Systems typically cost $1,500-$4,000 installed and are inspected during construction or remodel permitting.
Higher mounting requires more CFM. For every inch above the recommended minimum (24 inches for under-cabinet, 30 inches for island), plan to add 5-10% more CFM. A hood mounted at 36 inches needs about 30% more CFM than the same hood mounted at 24 inches to capture smoke effectively before it escapes sideways.
Yes, significantly. Add 1 CFM per foot of duct over 10 feet, 25 CFM per 90° elbow beyond the first, and 40 CFM for the wall or roof cap. A hood with 18 feet of ducting and three elbows can lose 50-100 CFM of effective airflow vs the manufacturer's rating. Use 6-inch round ducting with the shortest possible run for best performance.
Ready to find the right range hood? Browse The Trade Table's curated range hood collection by size, mount type, and CFM rating. Choose ductless range hoods for condos and retrofits without ductwork, or wood range hoods and copper range hoods for design-focused remodels. Pair with matching ranges — gas, electric, dual fuel, or induction — for a complete kitchen package. Free shipping, authorized dealer status, and price match guarantee on every model.
Ducted vs ductless range hood — compare ventilation performance, cost, installation, and noise to find the right range hood for your kitchen layout.
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This guide explains how to install a range hood step-by-step, including proper mounting height, ducting considerations, electrical connections, and common mistakes to avoid.
