Separate price movement from tax drag before you sell
Capital gains are not just “sell price minus buy price.” A professional estimate starts with cost basis, subtracts sale costs, classifies the holding period, then applies an estimated tax rate. The IRS explains the distinction between short and long term in Topic 409.
"The number that matters is after-tax cash kept, not the headline gain."
Basis First
Track purchase fees and basis adjustments. The IRS notes that basis often starts with cost and related purchase expenses in Topic 703.
Tax Only On Gains
The calculator applies tax only when realized gain is positive; losses may have separate offset rules.
Holding Period
Holding period can change treatment. Use the term flag as a prompt to check local rules before selling.
Frequently Asked Questions
It estimates cost basis, net proceeds, realized gain, tax on positive gain, and after-tax net gain. For U.S. context, compare the model with IRS Topic 409 and IRS Topic 703.
Cost basis is the purchase value plus costs connected with the purchase and any allowed basis adjustments. The calculator keeps those items visible so the tax estimate is easier to audit.
No. It is a planning model. Local rules can depend on asset type, residency, exemptions, loss offsets, reporting forms, and holding period.
