There are five free, ungated calculators for dental office projects: DSCR (does your cash flow cover the debt at the 1.25x coverage many lenders look for), loan payment with interest-only periods, operatories and square footage, TI allowance gap, and a Section 179 educational estimate for 2026. This page shows the formula behind each one. None gives a total project budget. For that, use the cost estimator or the Budget Plan.
What does each calculator do?
Pick the one that matches the question in front of you. Each calculator page explains how its result is calculated, and the formulas for all five are in the table below.
DSCR calculator
Divide the practice's cash flow by its annual loan payments, other debt and living costs. See how far you sit above or below the 1.25x benchmark before you talk to a bank.
Dental loan payment calculator
Monthly payment on any amount, rate and term, with an interest-only period at the start. Shows the payment during and after the interest-only months.
Operatory and square footage calculator
Turn your dentists and hygienists into an operatory range, then into usable and rentable square feet, using the same space-per-operatory assumptions as the Alithos estimator.
TI allowance calculator
Compare the landlord's tenant improvement allowance with your build-out cost and see the gap you fund yourself, plus the monthly payment on that gap.
Section 179 calculator
An educational estimate of how the 2026 federal limit, phase-out and bonus depreciation apply to equipment purchases, with a California option. Not tax advice. Confirm with your CPA.
Dental office cost estimator
An all-in planning range for a startup, relocation or ground-up build, with the monthly payment and the collections needed at 1.25x. It asks for your name, city and state, email and phone to unlock.
Cost benchmark table
The estimator's output for common office sizes and finish levels, in one table, with every assumption listed.
Which calculator answers your question?
| Your question | Use this |
|---|---|
| Will my cash flow cover the loan payments? | DSCR calculator |
| What is my monthly payment, including an interest-only start? | Loan payment calculator |
| How many square feet do I need for my operatory count? | Operatory and square footage calculator |
| Is the landlord's TI allowance enough? | TI allowance calculator |
| How does Section 179 work on new equipment? | Section 179 calculator |
| What will the whole office cost? | Cost estimator |
| What does a 3, 4 or 5 operatory office cost in the model? | Cost benchmark table |
| Is my specific project viable? | Feasibility Check ($2,500 flat, credits toward the Budget Plan) |
What formulas do the calculators use?
I show the math so you can check it, or rebuild it in a spreadsheet.
| Calculator | Formula |
|---|---|
| DSCR | Collections × (1 − overhead %) ÷ (annual loan payments + other annual debt payments + personal living costs) |
| Loan payment | Amortizing: P × r ÷ (1 − (1 + r)−n), with r the monthly rate and n the months left. Interest-only months: P × r |
| Square footage | Operatories (2 per dentist + 1.5 per hygienist + 0.5, rounded, minimum 3, shown as a one-op range) × sq ft per operatory (500 for 3-5 ops, 450 for 6-7, 425 for 8+). Rentable = usable × (1 + load factor) |
| TI gap | Sq ft × construction cost per sq ft (plus 10% for cabinetry if you include it) − sq ft × allowance per sq ft, never below zero |
| Section 179 | The smallest of the equipment cost, your business income and the federal limit of $2,560,000, which is reduced dollar for dollar once qualifying purchases pass $4,090,000 [2]. Any remaining cost is shown under bonus depreciation |
Here is how the pieces fit. The Alithos estimator puts a 4-operatory startup in leased space at standard finish at a point estimate of $784,800 on 2,000 sq ft. At its default loan of 15 years at 8.25%, that is about $7,614 a month. Multiply the annual payment by 1.25 and you get about $114,205 a year of cash flow the practice needs for debt alone. Those are planning assumptions, not a quote or survey data. The SBA allows 7(a) terms up to 25 years for real estate and generally up to 10 years for equipment and working capital [3], so your actual term may differ.
How do these calculators work?
- In your browser. The math runs on the page. You don't enter a name or email to use them.
- One question each. They never output a total project budget. That is the estimator's job, and for your project, the Budget Plan ($7,500-$10,000 flat fee, scope in writing).
- Planning math, not advice. I'm not a lender, CPA, attorney, contractor or architect. Lenders set their own rates and thresholds. Tax results are educational: California, for example, limits Section 179 to $25,000, phasing out above $200,000 of purchases, and does not follow federal bonus depreciation [4]. Confirm with your CPA.
- Dated and sourced. Defaults come from the estimator assumptions and from primary sources, re-checked on the schedule in the editorial policy.
For the bigger picture, the planning guides cover startup costs and financing. If you'd rather talk your numbers through, book a free Project Fit Call.
Common questions
Are the calculators really free?
Yes. There is no email gate and no sign-up. Open a calculator, type your numbers and read the result.
Will a calculator tell me what my dental office will cost?
No. Each one answers a single question, like a payment or a coverage ratio. For an all-in range, use the cost estimator on the homepage. For a line-item budget built on your project, that is the Budget Plan.
Can I use a calculator result with my bank?
Use it to prepare for the conversation, not to replace it. Each lender sets its own rates, terms and coverage thresholds, so ask each one for its numbers.
Does the Section 179 calculator tell me what I can deduct?
No. It is an educational estimate of how the federal limit and phase-out work for the 2026 tax year. Your deduction depends on your entity, income, state and elections. Confirm with your CPA.
Sources
- ADA News, M. Jerkins, "Ask the Expert: How much debt is too much when buying a dental practice?" (2026). adanews.ada.org
- IRS, Rev. Proc. 2025-32, section 4.24 (2025). irs.gov
- U.S. Small Business Administration, 7(a) loan program: terms, conditions, and eligibility (accessed 2026). sba.gov
- California Franchise Tax Board, 2025 Instructions for Form FTB 3885A (2025). ftb.ca.gov
- Alithos estimator assumptions and benchmark table (2026). alithos.co/cost-benchmark
Written by Dan Ellyson. Model figures are planning assumptions from the Alithos estimator, not quotes. Tax and lending figures were checked against the sources above on October 31, 2026. How we research and update this page.