Sheet set — 15 tools, no signup

Run the numbers before you run the paperwork.

Twenty free calculators for buying, saving, and refinancing — mortgage payment, affordability, extra-payment savings, rent vs. buy, refinance breakeven, a down-payment savings plan, debt-to-income ratio, temporary rate buydowns, condo reserve warrantability, escrow shortages, the two-ratio test for non-occupant co-borrowers, the real cost of 5% vs. 20% down, HELOC vs. cash-out refinance, self-employed qualifying income, and the Social Security gross-up. Everything runs in your browser; nothing you type is stored.

Built and reviewed by Kulasekar Mittapalli, licensed Mortgage Loan Officer · Last reviewed September 2, 2026 · How these numbers are calculated

Estimates only — always confirm final numbers with your lender.

Sheet 01 — Monthly Payment

Home price

Down payment

Rate (APR %)

Term (years)

Est. monthly payment (P&I)

$0.00

Loan amount: $0

Total interest: $0

Every calculator

Pick a tool below — each opens its own page with the full breakdown.

Mortgage Payment

Full breakdown of principal & interest, taxes, insurance, HOA dues, and PMI — plus the complete amortization schedule.

Open calculator → 02

Extra Payments

See exactly how much interest and time you cut off your loan by paying a little extra toward principal each month — or with occasional lump sums.

Open calculator → 03

Affordability

A quick read on what you can reasonably afford, using the standard 28/36 rule lenders use for housing and total debt ratios.

Open calculator → 04

Rent vs Buy

Compares the total cost of renting against buying over time, accounting for appreciation, maintenance, and what your down payment could otherwise earn invested.

Open calculator → 05

Refinance

Weighs your current loan against a new rate and closing costs, and shows exactly how many months until refinancing pays for itself.

Open calculator → 06

Savings Goal

Work out how long it'll take to hit your down payment target — or how much to set aside monthly to get there by a chosen date.

Open calculator → 07

DTI Ratio

The single number most lenders check first. See both your front-end (housing-only) and back-end (total debt) ratios, and where they fall against typical lending thresholds.

Open calculator → 08

Buydown

See what a seller- or builder-paid temporary rate buydown actually saves you month to month, and roughly what it costs to fund.

Open calculator → 11

Student Loan RAP

Your monthly payment under the federal Repayment Assistance Plan, from the official tier table — plus the plan-choice traps that cost more than the payment itself.

Open calculator → 12

Condo Reserves

Check a condo building against the 15% HOA reserve threshold, delinquency and owner-occupancy limits that took effect August 2026 — before you write the offer.

Open calculator → 13

Escrow Shortage

Work out why your payment jumped, how large the shortage is, and what the monthly figure looks like spread over 12 months versus paid off at once.

Open calculator → 14

Property Analyzer

Enter an address to pull the property record and rent estimate, then see rental cash flow, cap rate, and how buying compares against renting and investing the difference.

Open calculator → 15

Seller Concessions

The seller nets the same either way — see whether the money is worth more as a price cut, permanent rate buydown, 2-1 buydown, or closing costs.

Open calculator → 16

Non-Occupant Co-Borrower DTI

A parent co-signing? Lenders check two ratios — everyone combined, and you alone. See both against Fannie Mae’s 43% and 50% thresholds, by underwriting path.

Open calculator → 17

Down Payment Size

5%, 10%, 15%, or 20% down, scored on total cost over your holding period — with PMI and what the cash you keep would earn. Bigger isn’t automatically better.

Open calculator → 18

HELOC vs. Cash-Out Refi

Refinance the whole loan, or keep your rate and add a HELOC? Total cost over your hold, plus the HELOC rate at which the answer flips.

Open calculator → 19

Self-Employed Income

Two years of returns, three possible qualifying figures. See which one applies to your trend — and the housing payment each supports.

Open calculator → 20

Social Security Gross-Up

The gross-up is 3.75%, not the 15% everyone quotes. See what your benefit counts as with and without documentation.

Open calculator →

Free · one page · no sales calls

The four questions most borrowers never think to ask

Published guidelines are not the rules you’re judged by. Your lender’s own credit policy is, and nobody publishes it. Get the question sheet:

What to ask about DTI, with the number in it, so you get a number back
How to find out whether a rule is the agency’s or the lender’s
What a “no” actually means, and when to take the same file elsewhere

Check your inbox. Click the confirmation link and the question sheet arrives right after. If it isn’t there in a minute, look in spam — that’s where it usually is.

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Which calculator answers which question

The tools split roughly into three stages. Before you shop: affordability and DTI establish your range and tell you what a lender will see. The down payment savings tool handles the timeline to get there.

While you're deciding: the payment calculator gives full PITI with an amortization schedule, rent vs. buy tests whether purchasing beats renting on your actual horizon, and the buydown and rate lock-in tools price the specific structures a seller or lender may put in front of you.

After you own: refinance breakeven, extra payment savings, PMI removal timing, escrow shortage diagnosis. Condo reserves sits slightly apart — it screens a building rather than a loan, which matters before you write an offer on a unit.

What they assume

Every tool states its assumptions inline and lets you replace them. Defaults are plausible starting points, not predictions — property tax, insurance, and mortgage insurance vary enough that any default will be wrong for most people. The formulas and their limits are documented in how we calculate these numbers.

Nothing you type is stored or transmitted. Every calculation runs in your browser.