Freelancer Quarterly Tax Calculator Scenarios and Practical Examples
このシミュレーションでは、想定フリーランス総収入、経費控除、基礎控除、四半期ごとの4回分割払いが納税額に与える影響を検証します。
フリーランスの報酬から何％を税金用に確保すべきか？
各請求額から一定割合（通常20%〜30%）を取り分け、個人事業主税と所得税の支払いに備える適切な準備率を解説します。
四半期予定納税額の計算手順と仕組み
総収入から必要経費の控除、92.35%課税対象基準、15.3%自営業税、基礎控除、四半期4分割計算までの手順を解説します。
収入変動が四半期納税額に与える影響の比較
年収3.5万ドル、8万ドル、15万ドルの3段階で比較し、累進税率と経費率が四半期納付額に及ぼす影響を比較します。
How Freelancer Quarterly Tax Estimation Works
Unlike traditional W-2 employees whose employers automatically withhold income and FICA payroll taxes each pay period, independent contractors (1099 freelancers) receive gross compensation and are responsible for paying their own taxes. The HelloTools Freelancer Quarterly Tax Calculator estimates these obligations across two core tax components:
1. Self-Employment Tax (SE Tax)
Covers Social Security (12.4% on 92.35% of net profit up to the annual cap) and Medicare (2.9% uncapped, plus 0.9% for high earners). The IRS allows you to deduct 50% of this SE tax when calculating your federal taxable income base.
2. Progressive Federal & State Income Tax
Calculated on net business profit after subtracting both the 50% SE tax write-off and your filing status standard deduction. Progressive federal brackets (10% to 32%) plus optional state tax are applied to this taxable base.
Model Assumptions & Exclusions
The calculator divides your estimated total annual tax burden into 4 equal quarterly voucher payments (traditionally due April 15, June 15, September 15, and January 15). It models federal progressive brackets, self-employment tax, standard deductions, and state tax rate presets. It excludes local city taxes, self-employed retirement plan contributions (SEP-IRA/Solo 401k), qualified business income (QBI) deductions, tax credits, and penalties.
四半期予定納税額をシミュレーションしてみませんか？
無料のフリーランス税金計算機で想定1099総収入、経費控除、申告区分を入力し、年4回の分割納税額を簡単に試算できます。