Run the numbers on any Zillow listing

Found a place you like on Zillow? This tool grabs the listing price, estimated rent, HOA, and property tax — then opens the calculator with everything filled in. One click, no typing.

1 Drag this button to your bookmarks bar

Zillow → Rent vs Buy

Drag the button above to your bookmarks bar.
Don't see the bookmarks bar? Press Ctrl+Shift+B (Windows) or ⌘+Shift+B (Mac) to show it.

On mobile or can't drag? Copy the bookmark manually

Create a new bookmark in your browser (any page is fine)
Edit the bookmark — change the URL to the code below
Name it something like "Zillow → Rent vs Buy"

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2 Go to any Zillow listing and click it

Browse Zillow like you normally would. When you're looking at a specific property, click "Zillow → Rent vs Buy" in your bookmarks bar.

A confirmation dialog will show you what it found:

Zillow -> Rent vs Buy
Price: $1,149,000
Rent Zestimate: $4,671/mo
HOA: $694/mo
Property Tax: 1.17%

988 Harrison St #SC8, San Francisco, CA 94107

Open calculator?

Click OK and the calculator opens in a new tab with the listing's price, rent estimate, HOA, and property tax already filled in. All other assumptions (stock returns, mortgage rate, time horizon, etc.) use the calculator defaults — adjust them to match your situation.

What it pulls from Zillow

Zillow field	Calculator field	Example
Listing price	Purchase price	$1,149,000
Rent Zestimate	Monthly rent	$4,671/mo
Monthly HOA	Monthly HOA	$694/mo
Property tax rate	Property tax %	1.17%

Everything else (down payment %, mortgage rate, stock returns, time horizon, etc.) uses the calculator's defaults. You can tweak any of them after importing.

Good to know

Does this send my data anywhere?: No. The bookmarklet runs entirely in your browser. It reads the Zillow page you're already looking at and opens our calculator — no data is sent to any server.
What if it says "Not a Zillow listing page"?: Make sure you're on an individual property page (like zillow.com/homedetails/...), not a search results page or Zillow's homepage.
What if Rent Zestimate shows "N/A"?: Some listings don't have a rent estimate. The calculator will still open with the other fields — just type in your own rent estimate.
Will this always work?: It depends on Zillow's page structure, which can change without notice. If it stops working, check back here — we'll update the bookmarklet.