Transparency & trust · reviewed October 10, 2026

Tax accuracy and review status

A calculator should be clear about what it knows. Supported cases are checked with automated fixtures; unusual cases remain outside the ordinary model.

2025 standard rules · 2026 form projections

What validation means

Unit tests check calculations and invariants. Browser checks test interaction, responsive layout and accessibility. Neither substitutes for a qualified professional reviewing the tax interpretation and complete filing behavior.

Year-specific status

2025 calculations reference published Form 8606 instructions. 2026 form behavior is provisional pending verification of final IRS instructions. Do not interpret a planning worksheet as a completed or accepted IRS filing.

Sources and next steps

Reviewed October 10, 2026. This independent educational website is not affiliated with the IRS. Special transactions need professional review.

Calculation methodology Authoritative sources and tax updates Tax and financial disclaimers