PITI and PMI math
Principal, interest, taxes, insurance, and PMI recalculated as buyers move the sliders, with an amortization summary.
The Problem
Buyers Leave to Do the Math Elsewhere
It happens on every listing page. A buyer sees the price, wonders about the monthly payment, and opens a bank's calculator in a new tab.
A buyer likes your listing and wants to know the monthly cost.
- Your page doesn't say, so they open a bank's calculator in another tab.
- It shows principal and interest only, without taxes, insurance, PMI, or the HOA fee.
- The number looks affordable until the lender's estimate arrives.
We start with the math your buyers need: principal and interest, property tax, homeowners insurance, HOA dues, and PMI when the down payment is under 20%.
On listing pages, it can pull price, tax, and HOA figures from your feed and let buyers adjust the rest. When they want the numbers emailed or a call from your lender partner, you get the lead. Buyers stay on your page, not a bank's.
The full monthly payment
Principal, interest, taxes, insurance, PMI, and HOA dues in one breakdown buyers can read.
Prefilled from your listings
Price, annual tax, and the HOA fee come straight from your IDX or RESO Web API feed.
Leads when buyers ask
Email-my-estimate and lender-call buttons capture the buyer's details at the right moment.
Our Calculator Build Process
From Loan Defaults to Your First Emailed Estimate in Five Steps
You approve the defaults, the disclosure text, and the design before launch. Your lender partner's compliance team signs off on anything that shows rates or payments.
What's Included
What You Get With Mortgage Calculators for Websites
Everything a buyer needs to judge a payment on your page: the math, the data, the design, and a way to reach you when they're ready.
Compare Options
DeveloperLook vs Free Calculator Widgets vs Lender-Provided Calculators
Free widgets cost nothing, and lender calculators come with rate data. Here's where each fits on an agent or broker site, and where each falls short.
| Feature | DeveloperLookBest fit | Free calculator widget | Lender-provided calculator |
|---|---|---|---|
| Payment breakdown | Full PITI plus PMI and dues | Often principal and interest | Varies by lender |
| Listing prefill | Price, tax, and dues filled in | Typed in by the buyer | Rarely tied to listings |
| Brand control | Your brand throughout | Provider's logo or link | Lender branding |
| Where leads go | Your CRM, plus lender by opt-in | Nowhere, or the provider | Straight to that lender |
| Rate data | Defaults you or a lender set | Generic defaults | Current rates from the bank |
| Disclosure wording | Approved by the lender | A generic disclaimer | Handled by the lender |
| Time to launch | 1 to 5 weeks | A few minutes | Days, if offered |
| Upfront cost | From $650, fixed scope | Free to use | Often free for partners |
DeveloperLook
Free calculator widget
- Payment breakdown
- DeveloperLook: Full PITI plus PMI and duesFree calculator widget: Often principal and interest
- Listing prefill
- DeveloperLook: Price, tax, and dues filled inFree calculator widget: Typed in by the buyer
- Brand control
- DeveloperLook: Your brand throughoutFree calculator widget: Provider's logo or link
- Where leads go
- DeveloperLook: Your CRM, plus lender by opt-inFree calculator widget: Nowhere, or the provider
- Rate data
- DeveloperLook: Defaults you or a lender setFree calculator widget: Generic defaults
- Disclosure wording
- DeveloperLook: Approved by the lenderFree calculator widget: A generic disclaimer
- Time to launch
- DeveloperLook: 1 to 5 weeksFree calculator widget: A few minutes
- Upfront cost
- DeveloperLook: From $650, fixed scopeFree calculator widget: Free to use
DeveloperLook
Lender-provided calculator
- Payment breakdown
- DeveloperLook: Full PITI plus PMI and duesLender-provided calculator: Varies by lender
- Listing prefill
- DeveloperLook: Price, tax, and dues filled inLender-provided calculator: Rarely tied to listings
- Brand control
- DeveloperLook: Your brand throughoutLender-provided calculator: Lender branding
- Where leads go
- DeveloperLook: Your CRM, plus lender by opt-inLender-provided calculator: Straight to that lender
- Rate data
- DeveloperLook: Defaults you or a lender setLender-provided calculator: Current rates from the bank
- Disclosure wording
- DeveloperLook: Approved by the lenderLender-provided calculator: Handled by the lender
- Time to launch
- DeveloperLook: 1 to 5 weeksLender-provided calculator: Days, if offered
- Upfront cost
- DeveloperLook: From $650, fixed scopeLender-provided calculator: Often free for partners
Projects We've Built
Finance and Property Sites We Have Built
Finance and property websites from our portfolio. A calculator sits on sites like these as a listing section, a standalone page, or an embed.
Investment Website Design & Development
- Finance
- Website
Finto Corporate Website Design & Development
- Finance
- Website
DWLFNDR Real estate Website
- Real Estate
- Website
HavenHues Real estate Website
- Real Estate
- Website
What Our Clients Say
What Clients Say After Launch
Feedback from teams we have built websites and calculators for.
We had a pretty specific idea of what we wanted our website to become, but I wasn’t sure how easily we could explain all of it to a development team. There were quite a few moving parts, and we were working toward a deadline, so I expected a few things to get lost along the way. That never really happened. They understood what we were trying to achieve, kept us updated throughout the process, and got everything ready within the agreed timeline. The final site feels much easier to navigate, works beautifully on mobile, and is noticeably smoother for our customers. It was a huge relief seeing the original idea actually turn into the website we had in mind.
The mobile experience is probably my favourite part of the new site. We had spent a lot of time making sure the desktop version looked right, and the team kept pushing us to think about how everything would actually feel on a phone too. They were right. The navigation is clean, the interactions feel natural, and everything we’ve tested so far works exactly as it should. They also went through the links, forms, integrations, and other details more than once before launch, which I really appreciated. And even after going live, we could still reach out when something came up. The whole process felt friendly, organised, and surprisingly straightforward.
What I appreciate most is that the website is actually easy for us to manage now. We can update content ourselves instead of sending a developer a message every time we need to change something small. They also paid attention to the technical SEO side, which mattered to us because we didn’t want a new website to create problems for the traffic we already had. I’ve probably asked more questions than I should have since launch, but every question has been handled patiently and without any fuss. The team is easy to work with, they explain things clearly, and when we need something changed, they focus on getting it done rather than making the process complicated.
1,000+
Projects shipped
10+
Years of experience
Top 3%
Upwork Top Rated Plus
5 stars
Average review score
Work Culture
Why Brokers Trust Our Payment Math
A payment calculator is only useful if the number holds up when the loan estimate arrives. These habits keep yours accurate, compliant, and easy to trust.
Math checked against lenders
Defaults you control
Disclosures before launch
Tested on real phones
You own the calculator
A fixed price before we start
Overview
Who builds a custom mortgage calculator for website listing pages?
DeveloperLook builds a mortgage calculator for website listing pages, loan officer sites, and brokerages. Every build shows principal, interest, taxes, insurance, PMI, and association dues, and sends leads to your CRM. Larger builds prefill listing data and add a lender handoff. Builds start at $650, most go live in 1 to 5 weeks, and you own the code.
- Starting price
- From $650 USD, fixed scope after discovery
- Typical timeline
- 1 to 5 weeks, by plan
- Experience
- 10+ years of development experience and 1,000+ shipped projects
- Post-launch support
- 30, 60, or 90 days, by plan
4 more facts
- Service
- Mortgage payment calculators (PITI, PMI, leads)
- Platforms
- WordPress, Webflow, Next.js, or any site
- Built with
- React, TypeScript, RESO Web API, CRM APIs
- Communication
- Calls in US, UK, and AU business hours
Your listing pages show a price and nothing else. Buyers leave to run the numbers on a bank's calculator and don't come back.
You want a mortgage calculator for website visitors that carries your brand and captures their details. Generic widgets show another company's logo instead.
Your brokerage works with a preferred lender. You want listings to show a payment and offer a lender introduction the way your compliance team approves.
Your buyers budget on principal and interest alone, then balk at taxes, insurance, PMI, and association dues. You want the full payment shown up front.
Your agency needs calculators for several realtor and lender clients. You want one tested build you can restyle, embed, and support under your brand.
You need live rate quotes or loan approvals online. That's a lender's application system, while our calculator estimates payments and hands buyers to your lender.
Your budget is under $650 and a free widget will do. A free calculator is a cheaper start, though it usually carries the provider's branding, and we'll say so.
Your goal is listings, not buyers, and you want owners asking what their home is worth. Our Home Valuation Lead Magnet Development page covers that tool.
You want campaigns that bring more buyers to your listings each month. Our Real Estate Lead Generation Services program runs those campaigns for you.
Not sure we're the right fit?
Send a two-line brief. We'll tell you honestly whether we're the right team.
Pricing
Transparent Starting Prices for Payment Calculators
These are starting points in USD. Your final price depends on how many calculators you need, listing prefill, and lender links, and you get a fixed proposal after a free calculator review.
Branded Calculator
For agents and brokers who want one payment calculator on their own site.
$650
- PITI payment math with PMI and HOA dues
- Styled to your brand, built for phones
- Embed on your listing template or any page
- Email-my-estimate lead capture
- Leads sent to your CRM
- 30 days of post-launch support
Listing Payment Suite
For teams that want payments prefilled on every listing and a lender handoff.
$1,550
- Everything in Branded Calculator
- Price, tax, and dues prefilled from your feed
- Home affordability calculator
- Lender partner card with approved disclosures
- Leads routed to agent and lender
- 60 days of post-launch support
Lender Calculator Platform
For lenders and brokerages that need several calculators and admin control.
$3,200
- Everything in Listing Payment Suite
- Refinance and rent-versus-buy calculators
- Admin panel for rates, terms, and PMI factors
- Branding per agent or branch
- Lender rate feed, where available
- 90 days of post-launch support
For Agencies
White-Label Calculators for Agencies With Realtor and Lender Clients
You own the client relationship. We build the calculator, connect the listing feed, and set up lead routing under your brand. One tested build can be restyled for each realtor or lender client you add.
Stay client-facing
Tested math
Senior engineering
Flexible capacity
How the partnership works
Send the client's site, listing feed, and lender details, and we reply with scope and price.
We build the math, the design, and the lead routing, then test all of it.
Your team launches it, and we stay on call for fixes during the support window.
Partner with DeveloperLookDelivered under your brand
The Right Technology for Your Project
Technology Stack
We build calculators as fast, accessible web components, feed them listing data, and send every lead to the CRM you already use.
React
TypeScript
JavaScript
Tailwind CSS
WordPress
Webflow
Next.js
Vercel
- RESO Web API
- IDX feed
Node.js
PostgreSQL
- Follow Up Boss
HubSpot
Google Analytics (GA4)
Google Tag Manager
FAQ
Frequently Asked Questions
Straight answers on cost, payment math, lender partners, disclosures, and branding for agents, brokers, and lenders.
Custom calculators start at $650 for one branded payment calculator with PITI math, PMI, and HOA dues. A listing suite with prefilled data, an affordability tool, and lender handoff is $1,550, and a multi-calculator platform for lenders starts at $3,200. You get a fixed proposal after the free calculator review.
A mortgage calculator for website listings usually goes live in 1 to 5 weeks. A single branded calculator takes about a week, and listing prefill with lender handoff takes 2 to 3 weeks. Multi-calculator platforms take 4 to 5. If your IDX provider limits custom scripts, we check the embed options first.
An embedded calculator answers the buyer's next question on your page instead of a bank's. An interactive real estate mortgage calculator keeps buyers adjusting down payments and terms on your listing, so visits last longer. The lead comes when they ask to email the breakdown or talk to a lender, a moment you'd otherwise miss.
The calculator recomputes every figure each time a buyer moves a slider. Principal and interest use the standard amortization formula on the loan amount, rate, and term. Annual tax and insurance are divided by 12, and HOA dues come from the listing. PMI usually applies to conventional loans with less than 20% down, using a factor the lender provides.
Yes, through a lender card, a rate feed, or a lead handoff to the lender's system. Co-marketing falls under RESPA Section 8, which bans referral fees but allows payment for services actually performed. So your broker and the lender's compliance team approve the setup, and we build what they approve.
We build the mortgage calculator widget for website pages as a web component that takes your fonts, colors, and spacing, so it looks native. Styles live in one place, so a rebrand is a quick change. It runs on WordPress, Webflow, Next.js, and IDX templates that allow custom scripts.
They often do when a rate or payment appears by default. Under Regulation Z, an ad that states a rate must show it as an annual percentage rate. A stated payment amount triggers disclosure of the down payment, repayment terms, and APR. So your lender sets any default rate and the disclosure text.
It follows the federal rules for conventional loans. Borrowers can ask to cancel PMI when the balance is scheduled to reach 80% of the home's original value, and servicers must end it at 78%. The amortization view marks the month PMI drops off, so buyers see the full picture.
They go to your CRM, your lender partner, or both, based on what the buyer asks for. Email-my-estimate requests reach your CRM as buyer inquiries with the listing and payment attached. Lender calls go to the lender only when the buyer opts in on the form.
You own the code, the settings, and the embed from launch day. It runs on your site or your hosting, with no per-view fees from us. Support lasts 30, 60, or 90 days by plan, and any later changes are quoted in writing before we start.
Book a call
Book Your Exclusive Strategy Session Today!
Pick a 30-minute slot that works for you. We meet on Google Meet to align on goals, scope, and the right next step.