Last updated: March 2026
Enter your AC unit dimensions and window measurements — the app checks opening size, mounting clearance, and support bracket requirements.
Whether it fits depends on measurements most people get wrong.
AC unit width (16–26") vs. window opening width, and sash opening height (must exceed unit height of 12–18")
Item: Window AC: 16–26" W × 16–24" D × 12–18" H (40–80 lbs). Portable AC: 14–18" W × 14–18" D × 24–34" H
Space: Standard double-hung window: 23–36" W opening. Sash opening height: 13–30"
Actual clear openings are usually 1–2″ smaller than the labeled size.
Your exact dimensions probably aren't "standard." Small measurement errors cause big problems — 1 inch can be the difference between fitting and getting stuck.
Verdicts are calculated by comparing all 6 item orientations against the space dimensions using verified building code standards. See our methodology
Takes 10 seconds · No signup needed
1 inch can be the difference between fitting and getting stuck.
“Checked 6 items against our new apartment in 10 minutes. Knew exactly what to order.” — New apartment
Measurements verified by the ItemFits engineering team · Based on IRC R311.2 · Our methodology
Standard sizes say it works — but your measurements are what matter.
Install the free ItemFits extension — it reads product dimensions on IKEA, Wayfair, Amazon and tells you if it fits before you buy.
Not all windows are big enough for furniture delivery. Here's how different window types compare — and which ones give you enough clearance.
Window delivery isn't a last resort — in some cities it's standard practice. Here's when removing a window is the best (or only) option for getting furniture inside.
Most window AC units require a window opening of 23–36 inches wide and at least 13–18 inches of sash opening height. A 5,000–8,000 BTU unit is typically 16–21" wide and fits windows as narrow as 23". Larger 12,000–18,000 BTU units are 22–26" wide and need wider windows. Check the unit's spec sheet for minimum window width.
Standard window AC units are designed for double-hung or single-hung windows and do not fit casement (crank-out) windows. For casement windows, use a portable AC with a window exhaust hose adapter kit, or look for specialized casement-window AC units (less common and more expensive).
Many cities (including New York City) require exterior support brackets for all window AC units above the first floor. Even where not legally required, a bracket is strongly recommended for units over 50 lbs. Brackets cost $20–$60 and mount to the exterior wall below the window sill.
Small units (5,000–8,000 BTU) weigh 40–55 lbs. Medium units (10,000–12,000 BTU) weigh 55–70 lbs. Large units (14,000–18,000 BTU) weigh 65–80 lbs. Portable floor units with exhaust hoses weigh 50–80 lbs but sit on the floor and only need a small window opening for the 5" exhaust hose.