These free tax calculators answer the questions small business owners and freelancers ask us most: how much to set aside for taxes on 1099 income, whether an S-Corp election would pay off, what a New Jersey employee really costs, and what a late return will cost in penalties. Each one shows the formula and the 2026 figures behind it, so you can see how the number was reached.
Why we built them
Most online calculators give you a number and nothing else. Ours show their work. Every tool page explains the inputs, the rates it uses with links to the IRS, the Social Security Administration and New Jersey, Delaware and Wyoming sources, a worked example you can check by hand, and a plain list of what it leaves out. An estimate you understand is more useful than a precise-looking figure you cannot explain.
The calculators follow the services we offer. We keep the books and prepare tax returns for small businesses in New Jersey and online across the U.S., and we help founders abroad run U.S. LLCs. Many of the questions those owners ask are arithmetic once you know the right rates, so we put the arithmetic online.
Your numbers stay in your browser
Everything is calculated on your device. Nothing you type is sent to our servers, to analytics or to advertising platforms. We only record that a calculator was used, never the values. There is no sign-up and no email gate.
Which calculator to use
- Working for yourself? Start with the self-employment tax calculator for your yearly tax and quarterly payments. Once profit is steady, the S-Corp tax savings calculator shows whether an election is worth it.
- Hiring in New Jersey? The NJ paycheck calculator gives both the employee’s take-home pay and the employer’s full cost.
- Selling products? Use the NJ sales tax calculator, the profit margin calculator and, for marketplace sellers, the Etsy and Amazon profit calculator.
- Starting a company? The LLC cost calculator compares New Jersey, Delaware and Wyoming fees.
- Behind on a filing? The IRS penalty calculator estimates late filing and payment penalties, including the Form 5472 penalty.
Updated every January
Tax brackets, wage bases and state rates change every year. We update the calculators each January when the new figures are published, and sooner when a rate changes mid-year. Each tool shows the tax year it uses, currently 2026.
When an estimate is not enough
A calculator cannot see your whole return. When the number matters, for example before an S-Corp election, a first hire or a late filing, our tax planning work and monthly bookkeeping turn the estimate into a plan built on your real books. If you want to talk through a result, book a free 15 to 30 minute consultation.