Tender-offer net proceeds calculator
Gross is the easy number. Enter what you're selling and how you hold it, and estimate the tax and the after-tax number — the one to actually plan with.
Gross proceeds
Taxable gain
Estimated tax
Estimated net proceeds
Effective tax on gross
Simplified estimate: excludes AMT (relevant for ISO exercises you hold), the 3.8% NIIT, multi-state allocation, and grant-specific terms. ISOs sold in the window are treated as disqualified (ordinary), which this model approximates with your ordinary rate. Model the real number with an advisor or CPA before the window closes.
Reading the result
- The net number is the plan number. Diversification, the house fund, the cash runway — size them on net, not gross.
- Set aside the tax immediately. Capital gains usually aren't withheld; option spread is often under-withheld. Park the estimated tax in T-bills and pay the quarterlies.
- Instrument order matters. If you hold a mix, which lots and instruments you tender changes the blended rate — that's lot-level planning, and it's exactly what a specialist models. See the full guide, or your company's page: SpaceX, OpenAI.
Want the real number, not the estimate?
Get matched with a fee-only fiduciary who models tender decisions for a living — lots, AMT, states, and sizing. Free, no obligation.