Equity Option Breakeven Calculator
Share price needed for options to be worth exercising.
Find the share price needed for stock options to break even after exercise cost and tax. Enter strike price to see breakeven price and current paper value.
What this tool does
Stock options deliver value only when the share price rises above the strike price by enough to offset the tax liability triggered by exercise. This calculator estimates the breakeven share price—the point at which the after-tax proceeds equal zero—and models the current paper value of your option grant based on today's share price. The marginal tax rate is the primary driver of how much higher the share price must climb. The result illustrates the relationship between exercise costs, tax impact, and option worth under current conditions. This calculation assumes options are exercised immediately and tax is paid from proceeds; it does not account for vesting schedules, alternative tax treatments, employer withholding rules, or the timing of tax payments. Use this to model scenarios, not as a forecast of future value.
Enter Values
Value is unusually high — please double-check
People also use
Income
Equity Vesting Value Calculator
Estimate the annual and total value of an equity grant vesting on a schedule, including the after-tax take-home you'd actually keep.
Income
Capital Gains Tax Calculator
Calculate capital gains tax on a sale. See net proceeds after tax and effective return on cost basis. Enter sale price to see gross gain and tax owed.
Income
Consumption Tax Receipt Calculator
Split a tax-inclusive price into the pre-tax amount and the tax portion at any rate — the receipt math for VAT, GST, or sales tax.
Formula Used
Spotted something off?
Calculations or display — let us know.
Disclaimer
Results are estimates for educational purposes only. They do not constitute financial advice. Consult a qualified professional before making financial decisions.
10,000 options at a 5 strike with a 40% marginal rate need the share price to reach 8.33 just to cover exercise tax — at 8 today the options are net negative if exercised. Knowing the breakeven helps decide whether to exercise now, wait, or let them expire.
What the result means
Breakeven price is the share price needed for the options to be net positive after exercise tax. Paper value is the current intrinsic value if exercised today, after tax. A negative paper value means exercising now would lose money.
Long-term capital gains treatment after exercise is not modelled — the tool assumes worst-case ordinary-income tax. If your jurisdiction grants favourable treatment (ISOs, EMI), the breakeven is lower than shown.
Run it with sensible defaults
Using strike price of 5, total options of 10,000, marginal tax rate of 40%, current share price of 8, the calculation works out to 8.33. The defaults are meant as a starting point, not a recommendation.
The levers in this calculation
The inputs — Strike Price, Total Options, Marginal Tax Rate, and Current Share Price — do not pull with equal force. Not every input has equal weight. Adjusting one input at a time toward extreme values shows which ones move the result most.
How the math works
Breakeven price is strike divided by one minus the tax rate. Paper value at the current price is options times (current price minus strike) times one minus tax rate.
What the headline number hides
Gross pay, net pay, and what actually lands in your account can differ by thousands depending on tax code, benefits, pension contributions, and student loan deductions. This tool isolates one piece of that picture — always pair it with a take-home calculator for the full view.
What this doesn't capture
Tax bands, pension contributions, student-loan deductions, and benefits-in-kind sit outside this calculation. The figure is the headline; your actual position depends on local tax rules and personal circumstances. Pair with a dedicated take-home calculator for the full picture.
At a 40 tax rate and £5 strike price, your 10,000 options break even at 8.33 per share.
Inputs
This example uses typical values for illustration. Adjust the inputs above to match a specific situation and see how the result changes.
Sources & Methodology
Methodology
This calculator computes the share price at which exercising an equity option becomes economically worthwhile after accounting for tax. The breakeven price is calculated by dividing the strike price by one minus the marginal tax rate, reflecting the after-tax proceeds needed to justify exercise. The model assumes a flat marginal tax rate applied to gains and treats taxes as a simple percentage reduction on profit. It does not model transaction costs, exercise fees, time decay, dividend impacts, employment-related withholding requirements, or variable tax treatment across different holding periods. The paper value of unexercised options at the current share price is estimated by multiplying the total number of options by the current-price-minus-strike spread, then applying the same tax rate. Results depend entirely on the accuracy of the tax rate input and assumed share price movements.
References
Frequently Asked Questions
Why does breakeven move with tax?
EMI or ISO treatment?
When should I exercise?
What about exercise cost itself?
Related Calculators
Equity Vesting Value Calculator
Estimate the annual and total value of an equity grant vesting on a schedule, including the after-tax take-home you'd actually keep.
Capital Gains Tax Calculator
Calculate capital gains tax on a sale. See net proceeds after tax and effective return on cost basis. Enter sale price to see gross gain and tax owed.
Consumption Tax Receipt Calculator
Split a tax-inclusive price into the pre-tax amount and the tax portion at any rate — the receipt math for VAT, GST, or sales tax.
More Income Calculators
Income
After-Tax Yield Calculator
Calculate after-tax yield on bonds or savings by entering your pre-tax yield and marginal income tax rate to see the return you actually keep.
Income
Airbnb Income Calculator
Calculate Airbnb income with monthly and annual net estimates from nightly rate, occupancy percentage, cleaning fees, and operating costs.
Income
Airbnb vs Long-Term Rental Calculator
Compare net income from Airbnb short-term rental vs long-term rental strategies with this annual income calculator for the same property.
Income
Amazon Flex Pay Calculator
Calculate net Amazon Flex earnings after vehicle costs and self-employment tax reserve. Enter hourly rate to see annual net income and effective hourly rate.
Income
Annual Bonus Compound Calculator
Future value of investing annual bonuses over a career at expected return. Enter bonus after tax and years to see compound fv of investing every bonus.
Income
Annual Gift Tax Allowance Value Calculator
Calculate the cumulative tax saving from your annual gift tax allowance over multiple years by entering your allowance amount, tax rate, and time period.
Explore Other Financial Tools
Utilities
Gold Price Calculator
Calculate gold value from weight and market price. Supports grams, ounces, and tolas. Enter price per unit to see total value and price per gram equivalent.
Real Estate
Landlord vs Tenant Cost Comparison
Compare long-term financial position of buying a home vs renting an equivalent property and investing the deposit difference.
Planning
Fat FIRE Calculator
Calculate Fat FIRE number for luxurious early retirement. See the target amount and years to reach it with your contribution plan.