Methodology

Where the figures come from

Tax figures are taken from published IRS guidance and kept in data files, never written into the calculator code. When a threshold changes, one data file is updated and every page that uses it changes with it. Each figure is cited on the sourcespage, and each calculator shows when its figures were last verified.

Overtime Tax Deduction Calculator

1. Premium per hour. Only the premium portion of overtime pay qualifies — the extra half of time-and-a-half required under section 7 of the Fair Labor Standards Act. The calculator takes half of your regular hourly rate.
2. Qualified overtime. The premium per hour multiplied by your overtime hours for the year.
3. Annual cap. The deduction is capped at $12,500 for single filers and heads of household and$25,000 for married couples filing jointly. Married filing separately is not eligible.
4. Income phase-out. Above $150,000 of income ($300,000 for joint filers) the deduction is reduced by $100 for every $1,000, or part of $1,000, over the threshold. It cannot go below zero.
5. Estimated saving. The deductible amount multiplied by your marginal federal rate. That rate is looked up on taxable income — your income less the standard deduction for your filing status — using the 2026 federal brackets.

Mortgage Recast Calculator

1. New balance. Your balance less the lump sum. A lump sum larger than the balance pays the loan off and there is nothing to recast.
2. New payment. The standard monthly amortisation formula on the new balance, over the same remaining months at the same rate. All arithmetic is in whole cents, so a 360-payment schedule cannot drift.
3. Interest saved. Total interest over the remaining term before the recast, less total interest after it.
4. Fee payback. The recast fee divided by the monthly reduction, rounded up to whole months. Under12 months is treated as worth it — a rule of thumb, not a lender rule.
5. Extra-payment comparison. The same lump sum paid straight to principal keeps the payment and shortens the term instead.

Fees, minimum lump sums and which loan types can be recast are planning defaults drawn from published lender guidance. They are not a legal rule and not the policy of any one servicer, so the calculator asks you to confirm them with yours.

Reporting

From tax year 2026 employers report qualified overtime separately on W-2, box 12, codeTT. You claim the deduction on Schedule 1-A (Form 1040). It does not require you to itemise.

What an estimate leaves out

• State income tax. Most states have not conformed to the federal deduction, so state tax usually still applies.
• Social Security and Medicare (FICA), which still apply to the full overtime amount.
• Credits, other adjustments and anything else on your return.
• Your exact modified adjusted gross income. The calculator uses the total income you enter as a stand-in.

Corrections

If a figure looks wrong, please tell me. Corrections are checked against the source and published with the new verification date.