Homeowners get misleading spam mailers quoting low payments that exclude taxes and insurance, and struggle to compare refinancing vs recasting vs staying put with accurate total costs and break-even timelines.
User inputs current loan details (balance, rate, term, taxes, insurance, PMI). The tool instantly models refinance at current market rates (with closing costs amortized), recast with a lump sum, and extra monthly payments — showing true monthly cost, total interest paid, break-even point, and net savings over the loan life.
Freemium — free basic comparison, paid tier ($5-10/mo or $29 one-time) unlocks advanced scenarios, rate alerts when refinancing becomes worth it, and personalized action plans. Affiliate revenue from connecting users to vetted lenders.
Real pain but episodic — homeowners face this decision maybe 1-3 times in their life. The spam mailer frustration is genuine and the Reddit thread confirms confusion. However, it's not a daily burning problem; it's a high-stakes one-time decision. Pain is intense when active but the window is narrow.
~65M mortgage holders in the US. Target of 5.5%+ rate holders from 2022-2024 originations is roughly 10-15M households. At $5-29 price point, TAM is $50-400M. Realistically addressable market for an indie tool is much smaller — maybe $2-10M ARR ceiling without lender partnerships. Affiliate revenue from lender referrals could be significant ($200-500 per qualified lead).
This is the weakest link. Free mortgage calculators are everywhere. Users expect financial calculators to be free because the entire industry gives them away as lead-gen tools. Paying $5-10/month for a calculator you use once or twice is a hard sell. The $29 one-time is more realistic but still faces 'I can just use a spreadsheet' objection. Rate alerts add recurring value but competing with free services from Bankrate, NerdWallet. Affiliate/lender referral is the real money path, not consumer subscriptions.
This is fundamentally math + UI. Mortgage amortization, break-even analysis, and scenario comparison are well-understood calculations. A solo dev can absolutely build a polished MVP in 4-6 weeks. No AI needed, no complex integrations required for v1. Rate data APIs exist (Mortgage News Daily, Freddie Mac). The hardest part is making the UX clear and trustworthy, not the engineering.
The specific gap — unified refinance vs recast vs extra payments with true all-in costs — genuinely does not exist as a single clean tool. Every competitor siloes their calculators. Recast calculators are especially rare. However, the gap exists partly because incumbents make money from lender referrals and have no incentive to build a 'maybe don't refinance' tool. A new entrant building an honest comparison tool is swimming against the industry's business model.
Very low natural recurrence. You run the comparison, make your decision, and you're done for years. Rate alerts add some stickiness but don't justify monthly payments for most users. This is fundamentally a one-time-use tool trying to force a subscription model. One-time payment or affiliate model fits much better than SaaS.
- +Genuine gap in the market — no tool does unified refi vs recast vs extra payment with true all-in costs
- +Technically simple to build with high polish potential in short timeframe
- +Strong SEO opportunity around 'mortgage recast calculator' (low competition keyword)
- +Pain is real and validated by organic Reddit discussions with high engagement
- +Affiliate revenue from lender referrals can be very lucrative ($200-500/lead) if you build trust
- !Consumer willingness to pay for calculators is near zero — free alternatives dominate mindshare
- !One-time use pattern makes subscription model extremely difficult to sustain
- !Bankrate or NerdWallet could build this feature in a sprint if it gains traction — zero moat
- !Affiliate model requires lender partnerships and compliance overhead (RESPA regulations)
- !Seasonal/cyclical demand tied to rate environment — if rates stay high, refi interest dies
Suite of free mortgage calculators including refinance, amortization, and extra payment calculators. Industry standard for basic mortgage math.
Refinance calculator, mortgage comparison tools, and lender marketplace. Strong editorial content layer.
Detailed mortgage calculator with amortization schedules, extra payment modeling, and some refinance comparison features. Power-user favorite.
Mortgage payment calculator integrated with Zillow's property data. Includes taxes and insurance estimates pulled from property records.
Collection of specialized mortgage calculators including refinance break-even, extra payment, and basic comparison tools.
Single-page web app: user enters current loan details (balance, rate, term remaining, monthly taxes, insurance, PMI). Tool instantly shows 3 columns — (1) Stay Put with optional extra payments, (2) Refinance at current market rate with closing costs, (3) Recast with lump sum. Each column shows: true monthly payment (PITI), total interest over remaining life, break-even month, and net savings vs current. Add a simple slider for 'how long will you stay in this home?' that dynamically updates the recommendation. No login required. Ship in 3-4 weeks.
Free comparison tool → build SEO traffic and trust → monetize via lender affiliate referrals for users who decide to refinance ($200-500/lead) → add premium one-time purchase ($19-29) for PDF reports, multi-scenario modeling, and rate alerts → explore B2B licensing to financial advisors and real estate agents who need this tool for client conversations ($99-199/year per seat)
Affiliate path: 3-6 months (need SEO traction first). One-time purchase: 4-8 weeks post-launch if you have distribution (Reddit, Twitter, Hacker News launch). B2B licensing: 2-4 months of direct outreach to financial advisors. Fastest path to first dollar is a Product Hunt / Reddit launch with a $19 'pro' tier.
- “spam mail claims they can get me down to $1230/month which I know is excluding a bunch of taxes and such”
- “wondering if I'd be able to get under $1500/month again, or if I'd be better off recasting instead of refinancing”
- “we need to know your current taxes and insurance monthly cost”
- “by the time you pay closing costs on a refi, your total cost will be close to a wash”