The calculators your finance team charges $200 a month for
Twelve production-grade tools for the decisions that move real money — refinancing, debt, unit economics, invoicing, compliance and AI spend. No account, no upsell, and nothing you type ever leaves your browser.
Built for the decisions that are hard to reverse
Each tool replaces a spreadsheet you would otherwise build badly, or a subscription you would rather not pay for.
Refinance Calculator
Find out exactly how many months until a refinance pays for itself. Compares your current loan against a new one including closing costs, PMI and lifetime interest.
Debt Payoff Planner
Compare the debt snowball and debt avalanche methods across all your balances. See your payoff date, total interest saved and a month-by-month payment schedule.
Life Insurance Calculator
Calculate how much life insurance your family actually needs using the DIME method plus income replacement. Get a coverage figure and a recommended term length.
Solar Savings Calculator
Estimate solar panel system size, upfront cost after incentives, payback period and 25-year savings using your actual electricity bill and local sun hours.
Invoice Generator
Create and download professional PDF invoices in under a minute. Multi-currency, tax and discount support, custom logo, and nothing ever leaves your browser.
SaaS Metrics
Calculate MRR, ARR, net revenue retention, churn, LTV, CAC payback and the Rule of 40 in one place. Benchmarked against real SaaS ranges investors expect.
Privacy Policy Generator
Generate a complete, customised privacy policy for your website or app in minutes. Covers GDPR, CCPA/CPRA, analytics, advertising and cookie disclosures.
AI Cost Calculator
Estimate and compare the monthly cost of Claude, GPT and other LLM APIs. Model token usage, caching and batch discounts to find the cheapest model for your workload.
Five categories, one standard
Finance
Mortgage, debt, insurance and investment maths done properly — the same formulas lenders and advisors use, with every assumption visible.
4 toolsBusiness
Run the numbers founders, freelancers and finance teams actually get asked about: unit economics, pricing, invoicing and cash flow.
4 toolsLegal
Generate the compliance documents every website and app is legally required to publish — GDPR, CCPA and app-store ready.
1 toolDeveloper
Structured data, AI token budgets and technical SEO utilities built by engineers who ship production sites.
2 toolsEnergy
Model solar payback, energy savings and home upgrade economics with transparent, region-aware assumptions.
1 toolHow SkyZap compares
The three realistic options when you need to model a financial decision.
| SkyZap | Your own spreadsheet | Paid SaaS / advisor | |
|---|---|---|---|
| Cost | Free | Free | $40–$400 / month |
| Time to first answer | Under a minute | 1–4 hours | Days |
| Formula correctness | Documented and audited | Depends entirely on you | Usually correct, rarely visible |
| Your data leaves your device | Never | Never | Always |
| Signup / sales call required | No | No | Almost always |
| Explains what the result means | Yes, in plain language | No | Yes, for a fee |
| Export to CSV / PDF | Included | Yes | Often a paid tier |
Why these produce answers you can act on
No data ever leaves your device
Your salary, debts, client list and loan balances stay in your browser. There is no backend to leak them, because there is no backend.
Real formulas, shown openly
Every tool documents the maths it uses and the assumptions baked in. A calculator that hides its method is hiding something.
A verdict, not just a number
A break-even month is useless without interpretation. Each tool explains the output in plain language so you know what to do next.
Instant, every time
Static pages, deferred scripts, no signup wall and no email capture before results. Sub-second to interactive on a phone.
Export what you build
Amortisation schedules, payoff plans, metric sets and invoices export as CSV, HTML or print-ready PDF.
Guides that go deeper
Forty-eight long-form articles by named practitioners explain the decisions behind the numbers.
Everything else in the toolbox
Rent vs Buy
Should you rent or buy? This calculator compares total wealth under both paths including maintenance, taxes, closing costs and the opportunity cost of your down payment.
Freelance Rate Calculator
Work out the hourly rate you must charge to hit your target income after taxes, business costs, unpaid admin time and holiday. Includes day and project rates.
Business Loan Calculator
Calculate business loan payments, true APR including fees, total interest and a full amortization schedule. Compare term loans, SBA loans and equipment finance.
Schema Generator
Generate valid JSON-LD structured data for Article, FAQ, Product, LocalBusiness, HowTo, Recipe, Event and more. Rich-result ready and validated as you type.
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Start with the decision in front of you
Refinancing this month? Pricing a freelance project? Checking whether your unit economics survive a spreadsheet? Pick a tool and get an answer in under a minute.