v1.4 — LLM Pricing Database + 17 endpoints
Financial Calculations
as a Service
Accurate tax, mortgage, and business math — plus an always-current LLM pricing database for 40+ AI models. Integrate financial intelligence into your app in minutes.
Pricing
Start free. Scale when you need it.
Pro
$9/mo
- 1,000 requests/day
- All endpoints
- Priority support
- Usage analytics
Business
$29/mo
- 10,000 requests/day
- All endpoints
- SLA + priority support
- Usage analytics
Quick Start
Three steps: get a key, make a request, use the result.
curl
Python
JavaScript
# 1. Get your free API key curl "https://api.61tools.com/register?email=you@example.com" # 2. Calculate self-employment tax curl -X POST https://api.61tools.com/v1/tax/self-employment -H "Content-Type: application/json" -H "X-API-Key: YOUR_KEY" -d '{"net_income": 75000, "filing_status": "single"}' # Response { "se_tax": 10597.50, "se_tax_deduction": 5298.75, "net_earnings_for_se": 70687.50, "rate": "15.3%" }
AI Disclosure: Calculation logic in this API was developed with AI assistance. All formulas use standard financial and IRS-published methods. Results are for informational purposes only — consult a licensed tax professional or financial advisor for official guidance.
Endpoints
POST endpoints accept JSON body. GET shortcuts accept query params — great for browser testing. All require X-API-Key header or ?api_key= param.
GET
/register?email=your@email.com
Get a free API key instantly — use your real email
GET
/v1/tax/self-employment?net_income=75000&api_key=...
GET shortcut: SE tax (use URL params for quick testing)
POST
/v1/tax/self-employment
Self-employment tax (Schedule SE) — SE tax, deduction, net earnings
GET
/v1/tax/quarterly-estimate?annual_income=90000&api_key=...
GET shortcut: Quarterly estimated tax payments
POST
/v1/tax/quarterly-estimate
Quarterly estimated tax with due dates and safe harbor calc
POST
/v1/tax/capital-gains
Capital gains tax — short vs long-term rates, NIIT, net proceeds
POST
/v1/tax/w2-vs-1099
W-2 vs 1099 take-home comparison — all taxes included
GET
/v1/finance/mortgage-payment?loan_amount=400000&annual_rate=6.75&api_key=...
GET shortcut: Mortgage PITI payment
POST
/v1/finance/mortgage-payment
PITI mortgage payment — P&I, taxes, insurance, total interest
GET
/v1/finance/compound-interest?principal=10000&annual_rate=7&years=20&api_key=...
GET shortcut: Compound interest + milestones
POST
/v1/finance/compound-interest
Compound interest with monthly contributions and milestone projections
POST
/v1/finance/debt-payoff
Debt payoff timeline — months, total paid, total interest
POST
/v1/business/break-even
Break-even analysis — units, revenue, contribution margin
POST
/v1/business/profit-margin
Gross, operating, and net profit margins
GET
/v1/usage
Your API key usage stats — requests today, limit, total
POST
/v1/ratios/calculate
Financial Ratio Analysis — 15 ratios, health score (A-F), NAICS industry benchmarks (Pro+). Liquidity, profitability, leverage, efficiency.
GET
/v1/llm/models 🆕 No key needed
LLM Pricing Database — Always-current pricing for 40+ models. Filter by provider, vision support, context window. Free, open access.
GET
/v1/llm/models/{provider} 🆕 No key needed
Pricing for a specific provider — openai, anthropic, google, meta, mistral, deepseek, and more.
POST
/v1/llm/cost-estimate 🆕
Calculate exact cost for a model + workload. Supports cache and batch discounts. Returns daily/monthly/annual projections.
POST
/v1/llm/compare 🆕
Rank ALL models by cost for your workload. Sorted cheapest-first with vs-cheapest multiplier. Filter by provider, vision, context.
POST
/v1/llm/budget-threshold 🆕
Reverse calculator — given a monthly budget, how many requests/tokens can you afford per day on any model?
GET
/v1/llm/history 🆕 Pro+
Historical price change log — tracks when providers update pricing. Pro/Business tier only.
Financial Ratio API
Calculate 15 ratios from raw financials. No ticker symbol needed — works for any private company.
curl
# Register (free — 100 req/day) curl "https://api.61tools.com/register?email=you@example.com" # Calculate 15 financial ratios curl -X POST https://api.61tools.com/v1/ratios/calculate -H "Content-Type: application/json" -H "X-API-Key: YOUR_KEY" -d '{"revenue":500000,"cost_of_goods_sold":200000,"operating_expenses":150000, "interest_expense":10000,"net_income":85000,"cash_and_equivalents":50000, "accounts_receivable":75000,"inventory":0,"current_assets":200000, "total_assets":500000,"current_liabilities":100000, "total_debt":150000,"shareholders_equity":250000,"naics_code":"54"}' # Response (truncated) { "health_score": 78.0, "health_grade": "B", "liquidity_ratios": [{ "name": "Current Ratio", "value": 2.0, "formatted": "2.00", "interpretation": "Healthy — adequate short-term coverage" }], "profitability_ratios": [...] }
Add "naics_code":"54" (Pro/Business tier) to compare against 17 NAICS industry benchmarks. Free tool: 61tools.com/tools/financial-ratio-calculator