Free tools for vendors
BookNox publishes six free tools for the money side of independent service work: an invoice generator, two tax calculators, two fee calculators, and a signature generator. Every one is free, needs no account, and lives at booknox.com/tools with nothing to install and no email gate.
What's available
The current tools:
- Invoice generator, make a clean PDF invoice and download it: booknox.com/tools/invoice-generator
- SE tax calculator, self employment, federal, and state tax with QBI for all 51 states: booknox.com/tools/self-employment-tax-calculator
- Quarterly tax calculator, the IRS safe harbor math behind your four estimated payments: booknox.com/tools/quarterly-estimated-tax-calculator
- Stripe fee calculator, what a card charge actually nets after processing: booknox.com/tools/stripe-fee-calculator
- Fee calculator, what a percentage booking platform fee costs over a full year: booknox.com/tools/fee-calculator
- Signature generator, draw or type a signature and download it as a clean image: booknox.com/tools/signature-generator
Taxes: the two calculators that work together
Start with the SE tax calculator. Enter your net business income and it estimates self employment tax, federal income tax, and your state's income tax, then shows the quarterly payment that keeps you out of penalty range. Every state has its own page built from the real 2026 brackets.
The quarterly tax calculator picks up from there. It applies the IRS safe harbor rule (100% of last year's tax, or 110% if your AGI was over $150,000) so you know the minimum to send each quarter no matter how your income spikes across the year.
Fees: what platforms and processors really take
The Stripe fee calculator shows what a card charge nets after processing, both forward (what lands from a $1,000 charge) and reverse (what to charge so $1,000 lands). Card processing runs about 2.9% plus 30 cents per charge, and those fees are themselves a deductible business expense.
The fee calculator answers a different question: what a booking platform that takes a percentage of every booking costs you across a full year. Enter your average booking size and monthly volume and it annualizes the cut, which is the honest comparison against a flat subscription.
Invoices and signatures
The invoice generator produces a real PDF invoice you can download and send to a client, with no account and no watermark.
The signature generator turns a drawn or typed signature into a clean image file for documents you sign outside a formal esign flow. For client contracts, BookNox proposals carry the signature step inside the booking flow instead.
Why the tools are free
The tools run the same math BookNox uses inside the product. A vendor who outgrows one off invoices usually needs the full flow: quote, contract, deposit, and calendar in one link. That is the paid product, a flat $29 a month with no booking fee taken. The tools stay free either way.