Simple • Fast • Free
Find the right time, anywhere.
Practical time and date tools for international calls, meetings, travel, schedules, and everyday calculations.
Explore the toolsTools
Useful answers in seconds
Choose a tool below. Calculations run directly in your browser and do not require an account.
Time Zone Converter
Convert a date and time between common world time zones.
Best Time to Call
Find a comfortable calling window across two time zones.
Date Difference Calculator
Calculate the number of calendar days and weeks between dates.
Meeting Time Finder
Find overlapping daytime or work-hour windows in two locations.
Age Calculator
Calculate age in years, months, days, and total days.
Business Days Calculator
Count Monday-through-Friday days in a date range.
Countdown Calculator
See a live countdown to a future date and time.
Travel Arrival Time Calculator
Convert departure time plus travel duration into destination local time.
Guides
Helpful answers for real-world time questions
These guides explain common international time-zone questions and link to the calculators when you need a date-specific answer.
Best Time to Call Taiwan from California
See practical California-to-Taiwan calling windows for daylight and standard time.
Best Time to Call South Korea from California
See practical California-to-Korea calling windows for PDT and PST.
How Long Is 3 Business Days?
See weekday-by-weekday examples and learn how weekends affect a 3-business-day period.
Why Time Window Tools?
Time-zone math should not slow you down.
International calls, travel, and date calculations become surprisingly confusing when daylight saving time and calendar changes are involved.
Time Window Tools is built to give clear, practical answers quickly, with focused pages that explain what each result means.