Current Time & World Time Zone Converter (UTC, EST, PST, CET, IST, JST

World Time Zones, Coordinated Universal Time (UTC) & Longitude Offsets

The Earth is divided into 24 standard primary time zones, each approximately 15^ of longitude wide:

• **

• Coordinated Universal Time (UTC) Base Formulas**:

UTC Time = Source Local Time - Source UTC Offset

Target Local Time = UTC Time + Target UTC Offset

Δ t = Target UTC Offset - Source UTC Offset

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• Major Standard World Time Zones**:

• PST / PDT: UTC-8 / UTC-7

• EST / EDT: UTC-5 / UTC-4

• UTC / GMT (Coordinated Universal Time - London): UTC+0

• CET / CEST: UTC+1 / UTC+2

• GST (Gulf Standard Time - Dubai): UTC+4

• IST: UTC+5:30

• SGT / HKT: UTC+8

• JST (Japan Standard Time - Tokyo): UTC+9

• AEST / AEDT (Australian Eastern Time - Sydney): UTC+10 / UTC+11

• **

• The International Date Line**:

• Crossing from west to east subtracts 24 hours (-1 day); crossing from east to west adds 24 hours.

How to Use This Calculator

Enter your Source Time Hour (0-23 or 1-12) (e.g. 12 in hr), Source Time Minute (0-59) (e.g. 0 in min), Source AM / PM / 24-Hour — choose from PM (Afternoon / Evening), AM (Morning), 24-Hour Military Time, From Time Zone (Source) — choose from PST / PDT (UTC-8 / UTC-7) - Los Angeles, San Francisco, Vancouver, CST / CDT (UTC-6 / UTC-5) - Chicago, Dallas, Mexico City, EST / EDT (UTC-5 / UTC-4) - New York, Toronto, Miami, and To Time Zone (Target) — choose from IST (UTC+5:30) - India (New Delhi, Bangalore), UTC / GMT (UTC+0) - Universal Standard, EST / EDT (UTC-5 / UTC-4) - New York. Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Conversion factors (to SI base unit or reference unit):

PST_minus_8: -8.0

CST_minus_6: -6.0

EST_minus_5: -5.0

CET_plus_1: 1.0

GST_plus_4: 4.0

IST_plus_5_30: 5.5

SGT_plus_8: 8.0

JST_plus_9: 9.0

AEST_plus_10: 10.0

Worked Example

A software team in New York (EST) scheduling a live code release with their engineering office in Bangalore (IST) calculates that a 12:00 PM noon EST meeting translates to 10:30 PM IST on the same evening.

Understanding Your Result

This calculation gives a precise result based on the inputs you provided. For practical decisions, consider whether the result changes meaningfully with slight variations in your inputs — if a 5–10% change in input causes a significant output change, gather more precise input data before deciding. Use this tool to quickly compare multiple scenarios side by side.