Quarterly1099Calculator.com

1099 Quarterly Tax Calculator — Free 2026

Estimate what to pay each quarter. Includes self-employment tax (15.3%), QBI deduction (20%), and 2026 IRS due dates.

How Quarterly Taxes Work

Self-Employment Tax

15.3% on 92.35% of net SE income. Covers Social Security and Medicare. You pay both employer and employee shares.

Deductions

Deduct half of SE tax from AGI. Also eligible for 20% QBI deduction if net income is below thresholds.

Underpayment Penalty

Owe less than $1,000 at filing? No penalty. Owe more? Pay 90% of current year tax quarterly, or 100% of prior year tax (110% if your prior-year AGI was over $150,000), to avoid the penalty.