Free tools
Run the numbers before you file.
Calculators built on the actual statutes, IRS tables and state rules, each figure checked against the official source in October 2026. No sign-up.
Delaware Franchise Tax Calculator
This calculator works out your Delaware corporate franchise tax under both statutory methods, the authorized shares method and the assumed par value capital method, and tells you which one is lower. It is built for Delaware C-Corps with large share counts and small balance sheets, the startups that open a five-figure bill from Delaware and owe a few hundred dollars instead.
Open calculator →Texas Franchise Tax Calculator
This calculator estimates the Texas franchise (margin) tax a taxable entity owes on its 2026 or 2027 report, comparing the four margin methods and the EZ computation side by side. It is for corporations and LLCs doing business in Texas, including Delaware companies registered in Texas, that want to know whether they owe anything above the $2.65 million no-tax-due threshold and which form gets them the lowest number.
Open calculator →83(b) Election Deadline Calculator
Enter the date your restricted stock was transferred and this tool returns the last day to file your Section 83(b) election, 30 days later, moved to the next business day when that date falls on a weekend or federal holiday. It is for founders, early employees and advisors receiving unvested stock or early-exercising options, and it also tells you which IRS service center to mail to if you file on paper.
Open calculator →S-Corp Tax Savings Calculator
This calculator estimates how much a profitable single-owner LLC or sole proprietorship would save each year by electing S corporation status, after subtracting the added costs of payroll, a separate Form 1120-S and state S-corp taxes. It is for owner-operators of service businesses and small companies with steady profit, not for venture-backed startups, which generally need to stay C-Corps.
Open calculator →Estimated Tax Calculator
This calculator works out the quarterly estimated tax payments needed to avoid an IRS underpayment penalty, using the safe-harbor rules for individuals filing Form 1040-ES and for C corporations. It is for founders, freelancers and S-corp owners with income that has no withholding, and for C-Corps that have started to show taxable income.
Open calculator →R&D Tax Credit Calculator
This calculator estimates your federal research credit under the alternative simplified credit (ASC) method of IRC §41(c)(4), including the reduced-credit election and how much a qualified small business could apply against payroll tax. It is for startups and growing companies that pay engineers, scientists or contractors to build new products, processes or software.
Open calculator →Sales Tax Nexus Checker
This checker compares your sales into each state against that state's economic nexus threshold and flags where you likely need to register and collect sales tax. It is for ecommerce sellers, SaaS companies and other remote businesses selling across state lines that want a quick first pass before talking to an advisor about registration.
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