ShowMath calculators
Every calculator, one place.
Each tool shows the math, cites the formula, and gives you a number you can send to your accountant or lawyer. Free, no signup.
Business & SaaS
10 calculators
MRR growth, CAC/LTV, churn, runway, ESOP dilution — unit economics for operators and founders.
SaaS MRR growth rate calculator
MoM and YoY MRR growth — see the compounding difference between 5% and 10% monthly growth.
Customer Acquisition Cost (CAC) calculator
Fully-loaded CAC: sales + marketing spend ÷ new customers, with blended and paid-only views.
Lifetime Value (LTV) calculator
Gross-margin LTV = ARPU × gross margin ÷ churn — the real number, not revenue LTV.
LTV:CAC ratio + payback period
LTV-to-CAC ratio and months to recover CAC — the health metric every SaaS investor checks first.
Churn rate + cohort retention
Monthly and annual churn, retention curve, and net revenue retention from a simple cohort.
SaaS pricing ladder tester
Starter / Pro / Enterprise mix — see how tier pricing and adoption % drive blended ARPU.
Freemium conversion rate calculator
Free users × conversion % × ARPU − free hosting cost — does freemium beat trial for you?
Burn rate + runway calculator
Monthly burn, net of revenue and gross margin, against cash on hand — months of runway left.
Employee stock option dilution
How much new-round dilution costs employee option grants — pre- vs post-money dilution math.
ESOP vesting cliff calculator
Vested-share value across 4-year / 1-year cliff schedules — what you keep if you leave at month N.
Marketing
10 calculators
Paid ads ROAS, SEO content ROI, webinar break-even, and referral program math — real returns, not vanity metrics.
Google Ads ROI calculator
Clicks → conversions → revenue → profit — full Google Ads funnel with breakeven CR and profit ROAS.
Facebook / Meta ads ROAS
ROAS, profit ROAS, breakeven ROAS, CAC — real profitability on Meta spend after margin.
Email campaign breakeven
List size × open × click × convert — does the campaign actually profit after production cost?
Influencer partnership ROI
Creator fee + gifted product vs reach × engagement × conversion — what a post is really worth.
SEO content ROI calculator
Content cost vs 3-year compounding traffic — ROI of publishing N articles at $X over time.
Podcast sponsorship CPM
Effective CPM by slot type (pre/mid/post-roll) with conversion math — real cost per engaged listener.
Affiliate commission rate tester
What commission rate you can pay after margin + network fee — per-order and monthly net profit.
Referral program ROI + viral coefficient
Double-sided referral math with viral coefficient (K) — when your program is self-sustaining growth.
Brand vs performance budget split
Binet & Field 60/40 — stage-appropriate brand allocation with lift modeling on performance ROAS.
Webinar ROI calculator
Full webinar funnel (registrant → attendee → buyer) with breakeven sales and cost per sale.
Dev & engineering
10 calculators
Cloud costs, API pricing, on-call comp, server capacity, and tech debt ROI — the numbers engineering leaders actually need.
Cloud hosting cost estimator
AWS, GCP, Azure, DO, Fly — monthly cost per MAU by compute, bandwidth, DB, storage.
LLM API cost calculator
Claude, GPT-4o, Gemini, DeepSeek — cost per call, daily/monthly/annual with prompt caching.
Freelance dev hourly rate
What to charge per hour based on target salary + benefits + overhead + utilization + profit margin.
Server capacity planning
Servers needed for peak RPS with CPU/RAM math, utilization targets, and N+1 / 2N redundancy.
Database cost calculator
RDS, Aurora Serverless, PlanetScale, Supabase, Neon, Atlas — monthly DB cost with storage + reads + writes.
Load balancer breakeven
Self-hosted HAProxy vs managed AWS ALB / GCP LB / Cloudflare — where the crossover point actually is.
Tech debt ROI calculator
Turn a debt-fix project into a finance pitch: drag cost today, fix cost, payback months, ROI over 3 years.
On-call compensation calculator
Fair pay for 24/7 rotations — passive stipend + active page pay at 1.5-2x hourly base, benchmarked to industry data.
Engineering OKR velocity
Is your quarterly OKR feasible? Team capacity, KTLO drag, and burn-rate projection say yes or cut scope.
Code review cycle time cost
Quantify the hidden tax of slow code review — context-switch drag, DORA benchmarks, annual recoverable productivity.
Real estate
10 calculators
Buy, rent, flip, and hold math with every line-item cost that usually gets skipped.
Mortgage affordability (DTI-based)
Max home price using 28/36 front-end/back-end DTI rules, tax, insurance, and HOA.
Rent vs buy with opportunity cost
Multi-year rent vs buy, including the opportunity cost of tying up a down payment.
Closing cost estimator
Line-item closing costs — lender fees, title, escrow, taxes, recording — as % of purchase price.
HELOC payment calculator
Interest-only draw vs amortizing repay — monthly payment and lifetime interest on a HELOC.
Cash-on-cash return calculator
Investment property annual cash flow ÷ total cash invested — your real yearly yield.
Cap rate calculator
Net operating income ÷ property value — compare deals on a cash-only-no-financing basis.
House flip profit estimator
Purchase + rehab + holding + selling — project net profit on a flip at a target ARV.
Short sale vs foreclosure cost
Compare credit hit, deficiency, tax, and time cost of a short sale vs letting it foreclose.
Property tax by state/county
Estimate annual property tax using effective rates for the largest counties in each state.
Home insurance premium estimator
Rough annual homeowners premium from dwelling coverage, location, and deductible choice.
Retirement & investing
10 calculators
Project out decades — match contributions, Roth breakeven, RMDs, Coast FIRE, doubling time.
401(k) match optimizer
How much to contribute per paycheck to capture the full employer match — and how much you're leaving on the table.
Roth vs traditional IRA breakeven
Find the retirement tax rate at which a Roth and a traditional IRA break even.
Retirement savings gap calculator
Project your nest egg at retirement age vs what you need — see the monthly gap.
Social Security claiming age calculator
Compare lifetime benefit at 62, full retirement age, and 70 — including breakeven age.
RMD (required minimum distribution)
Your required minimum distribution from a traditional IRA / 401(k) using the IRS Uniform Lifetime Table.
Dividend reinvestment growth
Compound a dividend-paying portfolio with reinvestment over N years — income vs total return.
Tax-loss harvesting benefit
After-tax benefit of harvesting a paper loss — federal, state, and $3,000 ordinary-income offset.
Rule of 72 / doubling time
Quickly estimate how long it takes for an investment to double — Rule of 72 vs exact.
Coast FIRE age calculator
The age at which today's portfolio can coast to your number with no further contributions.
Early retirement withdrawal penalty
10% penalty + federal + state tax — net you'd actually get withdrawing early from a 401(k) or traditional IRA.
Legal
10 calculators
Estimate filing fees, support obligations, and the real cost of legal processes before you hire anyone.
Child support estimator
Estimate monthly child support using the income-shares model used by the five most populous states.
Alimony / spousal support calculator
Estimate spousal support using common state formulas — duration and monthly payment.
Small claims filing cost calculator
See total filing + service + judgment-collection cost before you sue in small claims court.
Divorce cost estimator
Contested vs uncontested, mediation vs litigation — estimate total divorce cost by path.
Statute of limitations lookup
Find the deadline to file a lawsuit by state and claim type (contract, injury, fraud, debt).
Lawyer hourly rate vs flat fee
Compare the total you'd pay under an hourly retainer vs a flat fee at your expected case length.
Patent filing cost calculator
USPTO fees + attorney drafting + maintenance — full cost to file and hold a utility patent.
Trademark registration cost calculator
USPTO TEAS Plus/Standard fees + attorney + classes — total cost to register a U.S. trademark.
LLC formation cost by state
Filing fee + annual report + registered agent + publication — what an LLC really costs to open and keep.
Will vs trust cost comparison
Attorney drafting + probate risk — compare the long-term cost of a will vs a revocable living trust.