Time Zone Converter

Time Zone Converter for the US — All Six Time Zones Explained

The United States spans six primary time zones: Eastern (ET), Central (CT), Mountain (MT), Pacific (PT), Alaska (AKT), and Hawaii–Aleutian (HAT). Most of the country observes Daylight Saving Time (DST) — clocks spring forward on the second Sunday of March and fall back on the first Sunday of November. Two notable exceptions: Arizona (except the Navajo Nation) stays on Mountain Standard Time year-round, and Hawaii never observes DST.

Key US Time Zone Differences

• New York (ET) → Los Angeles (PT): 3 hours behind. 9 AM New York = 6 AM Los Angeles. Schedule calls after 12 PM ET / 9 AM PT to catch both coasts in business hours.
• New York (ET) → Chicago (CT): 1 hour behind. 9 AM ET = 8 AM CT. Easy overlap — essentially the whole business day.
• New York (ET) → Denver (MT): 2 hours behind. Note: Arizona does not observe MDT in summer, so Denver–Phoenix differs by 1 hour during DST.
• New York (ET) → Anchorage (AKT): 4 hours behind. 9 AM ET = 5 AM AKT — Alaska is pre-dawn when New York opens.
• New York (ET) → Honolulu (HAT): 5–6 hours behind (6 in summer when ET is on EDT). 9 AM ET = 3 AM Honolulu — no practical business-hours overlap during standard East Coast hours.

US to International — Top Time Differences

• New York → London: London is 5 hours ahead (EST) or 4–5 hours (EDT/BST). Best call window: 9–11 AM ET, when London is 2–4 PM.
• New York → Paris / Berlin (CET): 6 hours ahead in winter, 5–6 in summer. Optimal: 9–11 AM ET = 15:00–17:00 CET.
• New York → Tokyo (JST, UTC+9): 14 hours ahead in winter, 13 in summer. With no overlap in normal business hours, evening US calls (6–7 PM ET) catch Tokyo at 8–9 AM next day.
• Los Angeles → London: 8 hours behind in winter, 7–8 in summer. 9 AM London = 1 AM Los Angeles — there is almost no same-day business-hours window. LA must use 8–9 AM PT to catch London's 4–5 PM.
• New York → Sydney (AEST): Sydney is 15–16 hours ahead. 6 AM ET = 9–10 PM Sydney. The only viable window is very early morning ET (6–8 AM) catching Sydney at end of business day.

DST Changeover Dates — US 2025 & 2026

• Spring forward 2025: Sunday 9 March at 2:00 AM → 3:00 AM
• Fall back 2025: Sunday 2 November at 2:00 AM → 1:00 AM
• Spring forward 2026: Sunday 8 March at 2:00 AM → 3:00 AM
• Fall back 2026: Sunday 1 November at 2:00 AM → 1:00 AM

The US changes clocks 2–3 weeks before Europe in spring, which temporarily shifts US–Europe differences by one hour. During this window, New York to London is only 4 hours instead of the usual 5.

Best Time to Call — Top 5 US International Routes

• New York → London: 9:00–11:00 AM ET. London is 2–4 PM — ideal afternoon for UK colleagues.
• New York → Paris/Frankfurt: 9:00–11:00 AM ET. CET is 3–5 PM, workable before European end-of-day.
• Los Angeles → London: 8:00–9:00 AM PT only. London hits 4–5 PM. Outside this window there is no same-day overlap.
• New York → Dubai: 7:00–9:00 AM ET. Dubai (UTC+4) is 3–5 PM — late afternoon, still in office hours.
• New York → Tokyo: 6:00–8:00 AM ET. Tokyo is 8–10 PM — post-business but reachable. Alternatively, 7–9 PM ET catches Tokyo at 9–11 AM next morning.

Frequently Asked Questions

How many time zones does the US have?

The contiguous US has four main time zones (Eastern, Central, Mountain, Pacific). Including Alaska and Hawaii, there are six. US territories add more: Puerto Rico and the US Virgin Islands use Atlantic Standard Time (UTC−4, no DST); Guam and the Northern Mariana Islands use Chamorro Standard Time (UTC+10, no DST).

Does Arizona observe Daylight Saving Time?

Most of Arizona does not observe DST and stays on Mountain Standard Time (MST, UTC−7) year-round. The exception is the Navajo Nation, which does observe DST. This means that for much of the year, Arizona shares the same time as Pacific Daylight Time (PDT), not Mountain Daylight Time (MDT).

What is the difference between EST and EDT?

EST (Eastern Standard Time) is UTC−5 and applies from the first Sunday in November to the second Sunday in March. EDT (Eastern Daylight Time) is UTC−4 and applies the rest of the year. The Eastern Time Zone simply switches between the two. "ET" refers to Eastern Time in general, regardless of which offset is currently in effect.

What time is it in California when it is noon in New York?

California (Pacific Time) is always 3 hours behind New York (Eastern Time), regardless of DST — both states observe DST simultaneously. So noon in New York = 9:00 AM in Los Angeles or San Francisco.