About Tax Debt Calc
Radif Partners turns the federal collection rules into arithmetic you can run yourself: the late filing and late payment penalties of section 6651, interest compounded daily at each quarter's published rate, the cost of each kind of payment plan, and the minimum offer in compromise that Form 433-A (OIC) produces once the county housing and transportation standards are applied. We represent no one before the IRS, sell no resolution service, pass no lead to any firm and never ask for a name, an e-mail or a phone number.
The gap this site fills
Search for an IRS payment plan or for tax debt relief and most results are articles without a single calculation, or pages built to collect a name and a phone number for a resolution firm, with "free consultation" buttons above any figure. The penalty and interest calculators that rank are run by firms with a call-now banner on top, and the offer in compromise calculators ask you to type your own allowable expenses, as if the IRS had not published them for every county. One blog still gives 120 days for a short-term plan, when the IRS says 180; another ranks with thresholds from 2012.
This site does better than the first Google result because it computes at once, with no name or phone number, what the debt costs day by day (the penalties of IRC section 6651 and interest at the published quarterly rates), the monthly payment and total cost of a payment plan with the fees in force, and the minimum offer in compromise worked out with the Collection Financial Standards of the county in force since June 29, 2026, where the IRS spreads these rules over a dozen pages with no calculation and firms keep them for the "free consultation" call.
Who publishes it
The site is published by Radif Partners, a company that builds calculators on public rules. It is not a tax resolution firm, a law firm, an enrolled agent, a lender or a debt settlement company; it is not run by or affiliated with the IRS, the Treasury or any government agency; it receives no commission, collects no lead and has no partner to send you to.
Radif Partners
49 rue du Ressort
63000 Clermont-Ferrand, France
contact@taxdebtcalc.com
What we rely on
The Internal Revenue Code sections that set each rule (6651 for penalties, 6621 and 6622 for interest, 6159 for installment agreements, 7122 for offers, 6502 for the collection period, 7345 for passports), and the IRS pages, forms and publications that apply them: the penalty pages, the quarterly interest rates, the payment plan and Simple Payment Plan pages, Form 656-B and Form 433-A (OIC), the Collection Financial Standards with the housing table of every state, and Publication 1494. All were read on October 20, 2026; each page lists the ones it uses.
What the site leaves out
Your balance is yours to enter: the site does not connect to your IRS account and cannot see payments, refunds or assessments. Business payroll taxes, state tax debts, bankruptcy and the judgment an offer examiner applies to a particular case are not modelled. The method page lists every rule, formula and simplification; the editorial policy explains corrections.
Contact
contact@taxdebtcalc.com, for corrections and sources. We answer questions about a rule, not about your own account.