Installed in a sliding window
See It Installed
Installed in an up-and-down single-hung window
Why It's Different
Most cat doors require cutting a hole in a wall or exterior door. Ours installs directly into your window — nothing permanent, nothing you can't take back.
No Drilling, No Cutting
Slides into your existing window frame. No tools, no hardware, no holes in your wall or door.
Adjustable Fit
Resizable to match a range of window heights for a snug, secure seal.
Renter & Apartment Friendly
Fully removable and reversible — leave your window exactly as you found it, and take the insert with you when you move.
Works for Catios
Use it to give your cat window access to an outdoor catio without a permanent structural cut-through.
Product Description
Our patented cat door window inserts are engineered for smooth sliding and secure closure, built to fit into sliding windows and up-and-down (sash) windows. No cutting, no drilling — it installs in the window opening itself, so there's no permanent change to your home. Easy to install, and even easier to remove.
Sizing & Fit
Both versions adjust to fit windows between 16 and 36 inches — the up-and-down version adjusts by width, the sliding version adjusts by height. The cat passage opening is 7 inches wide by 7¾ inches tall on every door.
Window bigger than 36 inches? 8-inch extension panels are sold separately (1 panel $16, 2 panels $32, 3 panels $48) to extend the fit range — see the extension panel installation video. Window smaller than 23 inches? A panel segment is removed during install (see the installation videos below). If you're not sure your window will work, message the shop before you buy.
See It in Action
Up & Down Window Installation (Single/Double-Hung)
Sliding Window Installation
Find Your Window Type or Use Case
Frequently Asked Questions
Can you put a cat door in a window?
Yes. Instead of cutting a hole in a wall or exterior door, the insert fits directly into your window opening, replacing the need for a permanent cut-through.
Do I need to drill or cut anything to install it?
No. The insert slides into the window opening and is secured without tools, drilling, or hardware. Nothing is permanently altered.
Will this work for a catio?
Yes — it can give your cat window access between your home and an outdoor catio without needing a permanent structural opening.
I rent my home — is this a safe option?
Yes. Because nothing is drilled, cut, or permanently attached, you can remove it and restore the window to its original state, which makes it a renter- and apartment-friendly way to add a cat door.
Can I take it with me if I move?
Yes. The insert isn't fixed to the window — you can remove it and reinstall it in a new home's window.
Does it work with sliding and up-and-down windows?
Yes, it's designed for both sliding windows and up-and-down (single-hung/double-hung) windows. See the sliding window and up-and-down window pages for installation details specific to each.
How much does it cost?
$90 per door, fits windows 16–36 inches. If your window is larger, 8-inch extension panels are available for $16–$48. See our Etsy shop or eBay listing for current pricing and options.