Why we built it
You should not need an account or a heavy app to calculate a date or pick lunch. USEOYO is an independently operated utility service designed to open quickly, provide a clear answer and let you move on.
Our principles
- Core tools work without an account.
- Calculations and file operations run in your browser whenever practical.
- Every page explains its method and limitations, and reported errors are reviewed.
- Advertising is kept visually separate from controls and results.
Operation and accountability
The USEOYO operator has maintained the Korean and English service since 2026. Send calculation, accessibility, privacy or copyright concerns to yk.kwon@outlook.com.