The Complete Tax Tools
Directory

TaxPreparerTools.com is a free toolkit built for CPAs, Enrolled Agents, tax preparers, and individual filers who need fast, accurate answers during the tax year. Every calculator uses current IRS figures, every decoder translates official codes into plain English, and nothing requires an account. The tools are grouped into four families: calculators for estimating tax and deductions, decoders for interpreting IRS notices and codes, lookups for rates and deadlines, and checklists for return-preparation workflows.

Tax calculators

Estimate federal liability, self-employment tax, deductions, and credits before you open the return.

• Federal Income Tax Estimator — full bracket and credit breakdown
• Self-Employment Tax Calculator — 15.3% SE tax and the deductible half
• QBI Deduction Calculator — §199A with 2026 OBBBA rules
• Capital Gains Tax Calculator — short/long-term rates plus NIIT
• Depreciation Calculator — MACRS, Section 179, and bonus
• Home Office Deduction — simplified vs actual-expense method
• Mileage Deduction Calculator — current standard mileage rates
• IRS Penalty Calculator — failure-to-file, failure-to-pay, interest
• Quarterly Estimated Tax — safe-harbor payment schedule
• AMT Calculator (Form 6251) — alternative minimum tax estimate
• Child Tax Credit Estimator — CTC, ACTC, and ODC
• Earned Income Credit (EITC) — estimate your 2026 EITC
• Education Credits — AOTC vs Lifetime Learning
• Itemized vs Standard — which deduction method wins
• Reasonable Compensation — S-corp owner salary support
• S-Corp Audit Exposure — reasonable-comp reclass risk
• Self-Employed Retirement — SEP-IRA vs Solo 401(k)

IRS decoders

Translate the codes and notices the IRS actually sends into clear explanations and next steps.

• IRS Notice Decoder — CP and LTR notices in plain English
• Transcript Code Decoder — TC 150, 846, 570, 971, and more
• E-File Reject Decoder — fix R0000, IND, and F-series rejects
• Tax Acronym Decoder — 130+ terms for preparers

Lookups & deadlines

• Tax Deadline Calendar — every 2025-2026 filing date
• State Tax Rate Lookup — income, sales, and property rates
• Property Tax Search — rates across 50 states and 300+ counties
• Refund Tracker & Timeline — when a refund should arrive
• Extension Toolkit — Form 4868 and 7004 with payment calc

Checklists

• Amended Return Checklist — Form 1040-X, step by step