Time Difference Calculator

Calculate time differences between two times with support for multiple modes: simple time calculations, timezone conversions, and work hours tracking.

Time Difference Calculator

Calculate time differences with precision and timezone support

Calculation Mode

Start Time

End Time

Start Date (Optional)

End Date (Optional)

Key Features

Precise calculations to the second

Multi-day time difference support

Timezone-aware calculations with UTC conversion

Work hours tracking and overlap detection

Three calculation modes: Simple, Timezone, Work Hours

Smart caching for preferences and work periods

Understanding Time Calculations

Simple Mode: Basic time difference between two times on same day

Timezone Mode: Accounts for timezone offsets and UTC conversion

Work Hours: Track multiple periods with overlap detection

Smart Caching: Remembers your preferences and frequently used settings

UTC Conversion: All timezone calculations convert to UTC first

Tips & Strategies

Global Meeting Planning: Use timezone mode to find optimal meeting times across continents

Work Hours Tracking: Add multiple periods with descriptive names for better time management

Quick Access: Frequently used timezone combinations are automatically saved

Business Coordination: Japan is 14 hours ahead of US Eastern Time (13 during DST)

Time Zone Offsets: Remember EST (-5), PST (-8), GMT (0), JST (+9) for quick reference

Work-Life Balance: Use work hours mode to track actual productive time vs. total time

Frequently Asked Questions

How accurate are the timezone calculations?

Our calculator uses standard timezone offsets (without DST) and is accurate to the second. For maximum accuracy during DST periods, manually adjust by ±1 hour.

Does the calculator save my preferences?

Yes! Your calculation mode, timezone selections, and work periods are automatically saved to your browser's localStorage for quick access next time.

What's the actual time difference between major time zones?

EST to JST: 14 hours ahead. PST to GMT: 8 hours ahead. EST to GMT: 5 hours ahead. CST to JST: 15 hours ahead. Use timezone mode for any combination.

Can I track frequently used timezone combinations?

Absolutely! The calculator automatically tracks your frequently used timezone combinations and shows them as quick-access buttons for faster calculation.

How does the work hours tracking mode work?

Add multiple time periods with names (meetings, work blocks, breaks). The system calculates total hours and automatically saves your periods for future use.

Can I schedule international meetings with this tool?

Perfect for international scheduling! Enter your time and timezone, then see what time it would be in your colleague's timezone. Quick access to frequent combinations included.

Is this tool suitable for freelancers and remote teams?

Ideal for remote work! Track work hours across time zones, schedule client meetings internationally, and manage distributed team coordination with smart caching.

What data is stored in my browser?

Only your preferences: calculation mode, timezone selections, work periods, and frequently used combinations. No personal data or calculation results are stored.