Ultimate Fee Calculator is a compensation calculation tool fully compliant with Japanese freelance practices. It allows unified management of compensation, net income, and work pace for all contract types, from "General (hourly rate/fixed fee)" to "SES (adjustment range)."

Key Features

• Two Calculation Modes: Supports General Mode (hourly rate/fixed fee) and SES Mode (adjustment range). Switch between them depending on your needs.
• Invoice System Compatible: You can enter the registration number of a qualified invoice issuer, which will be automatically reflected in the output text.
• Withholding Tax Calculation: Default settings according to job category (Engineer/Designer are ON, Writer/Other are OFF), and also supports the 20.42% logic for amounts exceeding 1 million yen.
• Automatic Business Day Calculation: In SES mode, it automatically calculates the number of weekdays (excluding Saturdays and Sundays) from today until the end of the month. Manual adjustment is also possible.
• Visual Range Gauge: In SES mode, visually displays progress. Color-coded for shortfall (red), safe zone (green), and exceeding (blue).
• Pace Advisor: Based on the remaining business days, it automatically calculates and advises the daily working hours required to reach the lower limit.
• Annual Income Conversion: Automatically displays annual income conversion based on current total billing (excl. tax) × 12 months. Helps boost motivation.
• 3-Way Copy: Output in 3 formats: Email, Excel (tab-separated), and Notion (Markdown table). Copy and paste to use immediately.
• Persistent Settings: Settings are automatically saved in localStorage. Previous settings are restored on your next visit.
• Time Input Format: In SES mode, actual hours can be entered in two formats: "190.25 hours" or "190 hours 15 minutes". They are converted in real-time.
• Crowdsourcing Fee Support: Platform fees for Crowdsourcing services like CrowdWorks and Lancers are reflected in calculations. Supports two input modes: rate (%) and fixed amount (¥). The rate is calculated based on the total amount including tax and is automatically deducted from the net income.

Privacy and Security

All calculations are performed strictly with fractions truncated, in compliance with Japanese tax practices.

• 2025-12-04Added crowdsourcing fee feature. Supports two input modes: rate (%) and fixed amount (¥). Settings panel made more compact with a 2-column layout. Improved time input separator for responsiveness (horizontal arrow ⇔ / vertical arrow ⇕).
• 2025-12-04Initial release. Implemented General/SES modes, invoice compatibility, withholding tax calculation, automatic business day calculation, Visual Range Gauge, Pace Advisor, annual income conversion, and 3-Way Copy features.