Selling and ecommerce

• EcommerceEcommerce profit calculatorProfit per order after product cost, platform fees, shipping and ads.
• EcommerceSeller fees by platformWhat Amazon, eBay, Etsy, Shopify, Stripe, PayPal and others charge U.S. sellers.
• EcommerceSales tax by stateThe statewide rate in all 50 states and D.C., with a purchase calculator.
• EcommerceBreak-even calculatorUnits you need to sell to cover fixed costs.

Marketing

• MarketingBreak-even ROAS calculatorThe return on ad spend you need before ads lose money.
• MarketingAd metrics calculatorCPM, CPC, CPA, click-through and conversion rate from campaign numbers.

Startups, AI and finance

• AIAI API cost calculatorMonthly cost of a workload on Claude, GPT, Gemini, Grok and DeepSeek models.
• StartupsSaaS metrics calculatorARR, lifetime value, LTV to CAC and payback from a few inputs.
• StartupsStartup runway calculatorMonths until the cash runs out, with optional growth.
• FintechIncome tax calculatorFederal, state and local income tax for 2025 or 2026 in all 50 states and D.C.
• StartupsBusiness tax calculatorFederal and state corporate income tax for a C corporation in any state.
• FintechBusiness loan calculatorMonthly payment, total interest and the first payments broken down.

Markets, trade and the economy

• MarketsTariff lookupU.S. import duty for a product in the official tariff schedule.
• MarketsMortgage calculatorMonthly payment with this week’s average 30-year rate filled in.
• MarketsInflation calculatorWhat an amount from an earlier year is worth today, overall and by category.
• MarketsCompany comparisonTwo companies’ latest quarterly results side by side, from SEC filings.

Company and security research

• Big TechCompany lookupOne company across every tracker: layoffs, funding, breaches, contracts and more.
• CybersecurityVulnerability lookupCheck whether a vendor or product is on CISA’s exploited vulnerabilities list.