EST to HST Converter
Convert time between Eastern Standard Time (EST) and Hawaii Standard Time (HST)
Eastern Standard Time (EST)
Hawaii Standard Time (HST)
Time Difference
Hawaii Standard Time (HST) is 0 hours ahead of Eastern Standard Time (EST)
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Select Time
Quick Reference
| EST | HST |
|---|---|
| 21:00 | 16:00 |
| 23:00 | 18:00 |
| 01:00 | 20:00 |
| 03:00 | 22:00 |
| 05:00 | 00:00 |
| 07:00 | 02:00 |
| 09:00 | 04:00 |
| 11:00 | 06:00 |
| 13:00 | 08:00 |
| 15:00 | 10:00 |
| 17:00 | 12:00 |
| 19:00 | 14:00 |
Top 10 Most Common Time Zones
| Abbreviation | Full Name | UTC Offset | Typical Use |
|---|---|---|---|
| UTC | Coordinated Universal Time | UTC ±0 | Global reference standard (servers, logs, APIs) |
| EST / EDT | Eastern (US) Time | UTC −5 / −4 | New York, Toronto — North American business hub |
| CST / CDT | Central (US) Time | UTC −6 / −5 | Chicago, Dallas — US central business region |
| PST / PDT | Pacific (US) Time | UTC −8 / −7 | San Francisco, Los Angeles — tech industry standard |
| GMT / BST | Greenwich Mean / British Summer Time | UTC 0 / +1 | UK, used globally as a reference with UTC |
| CET / CEST | Central European (Summer) Time | UTC +1 / +2 | Paris, Berlin, Amsterdam — EU business core |
| IST | India Standard Time | UTC +5:30 | India — major IT & outsourcing region |
| CST | China Standard Time | UTC +8 | Beijing, Shanghai — East Asia business hub |
| JST | Japan Standard Time | UTC +9 | Tokyo — finance & tech hub |
| AEST / AEDT | Australian Eastern (Daylight) Time | UTC +10 / +11 | Sydney, Melbourne — APAC regional business |
Why Time Zone Abbreviations Are Ambiguous
Unlike standardized identifiers (like America/New_York or Europe/London from the IANA tz database), abbreviations such as "CST" or "IST" are not globally unique. They can refer to different time zones depending on context — country, region, or even time of year (due to daylight saving time).
Common Ambiguous Time Zone Abbreviations
| Abbrev. | Common Meaning(s) | UTC Offset | Region(s) |
|---|---|---|---|
| CST | Central Standard Time / China Standard Time / Cuba Standard Time | UTC−6 / UTC+8 / UTC−5 | North America, China, Cuba |
| IST | Indian Standard Time / Irish Standard Time / Israel Standard Time | UTC+5:30 / UTC+1 / UTC+2 | India, Ireland, Israel |
| AST | Atlantic Standard Time / Arabia Standard Time | UTC−4 / UTC+3 | Caribbean, Canada, Middle East |
| PST | Pacific Standard Time / Philippine Standard Time | UTC−8 / UTC+8 | North America, Philippines |
| EST | Eastern Standard Time (North America / Australia) | UTC−5 / UTC+10 | North America, Australia |
✅ Best Practice
To avoid ambiguity, always:
- Use IANA tz identifiers — e.g.,
America/New_Yorkinstead of "EST" - Specify UTC offset explicitly — e.g.,
UTC−5when abbreviations must be used - Include the full timezone name — e.g., "Eastern Standard Time (EST)" with UTC offset
Related Time Zone Conversions
About EST to HST Time Conversion
Converting time between Eastern Standard Time (EST) and Hawaii Standard Time (HST) is essential for coordinating between the US East Coast and Hawaii. EST is UTC-5 (standard time, typically November to March), while HST is UTC-10 (year-round, Hawaii does not observe daylight saving time). EST is 5 hours ahead of HST during standard time. When daylight saving time is active on the mainland (March-November), the East Coast observes EDT (UTC-4), making it 6 hours ahead of HST.
This conversion is crucial for businesses operating between New York, Boston, Philadelphia, Miami, and Hawaii. Tech companies, financial services, tourism operations, and enterprises coordinating mainland east coast and island operations rely on accurate time conversions. Hawaii Standard Time is unique as it remains constant throughout the year without daylight saving adjustments. This makes the offset with mainland time zones inconsistent - during winter months (EST) the difference is 5 hours, but during summer months (EDT) the difference is 6 hours, requiring careful attention when scheduling calls and managing operations across both regions.
Common Use Cases for EST to HST Conversion
Business & Work
- Scheduling calls between New York headquarters and Hawaii branch offices
- Coordinating business operations between East Coast and Hawaiian locations
- Managing tourist operations and hospitality services across the mainland and islands
- Planning conference calls for companies with presence in both regions
Personal & Travel
- Coordinating with family and friends in Hawaii from the East Coast
- Planning travel between East Coast and Hawaiian destinations
- Scheduling virtual meetings with Hawaii-based relatives or business partners
- Arranging online collaboration with Hawaii-based colleagues
Time Zone Information
Eastern Standard Time (EST)
- UTC Offset: UTC-5
- IANA Timezone: America/New_York
- Daylight Saving: Standard time (first Sunday in November to second Sunday in March)
- Major Cities: New York, Boston, Philadelphia, Miami, Washington DC, Atlanta
- Coverage: Eastern United States and Canada (winter months)
Hawaii Standard Time (HST)
- UTC Offset: UTC-10
- IANA Timezone: Pacific/Honolulu
- Daylight Saving: No daylight saving time (consistent year-round)
- Major Cities: Honolulu, Hilo, Kailua, Maui, Kauai
- Coverage: All Hawaiian islands (consistent year-round)
Quick Reference: EST to HST
Remember: EST is 5 hours ahead of HST (during winter). When daylight saving time begins (second Sunday in March) and EST becomes EDT, the difference increases to 6 hours. Hawaii does not observe daylight saving time.
Frequently Asked Questions
What is the time difference between EST and HST?
Eastern Standard Time (EST) is UTC-5, while Hawaii Standard Time (HST) is UTC-10. EST is 5 hours ahead of HST. When it's 1:00 PM in New York (EST), it's 8:00 AM the same day in Honolulu (HST).
When is EST active and how does it affect Hawaii coordination?
EST is observed from the first Sunday in November to the second Sunday in March. During this period, the East Coast is 5 hours ahead of Hawaii. From March to November, when the East Coast observes EDT (UTC-4), the difference is 6 hours. This makes winter coordination (EST season) have a smaller time gap than summer coordination.
Does Hawaii observe daylight saving time like EST does?
No, Hawaii does not observe daylight saving time. Hawaii Standard Time (HST) remains UTC-10 year-round. This is why the time difference between Hawaii and the mainland varies - the mainland changes its clocks twice per year while Hawaii stays constant. EST is specifically the winter offset for the East Coast.
What major cities are in EST and HST timezones?
EST covers major East Coast cities including New York, Boston, Philadelphia, Miami, Washington DC, and Atlanta during winter months. HST covers all Hawaiian islands with major cities being Honolulu, Hilo, Kailua, Waihuku, and Kaneohe. These regions represent the US East Coast during winter and the Hawaiian Islands.
What are the best times to schedule calls between EST and HST regions?
The 5-hour difference during EST season provides limited overlap. Early morning EST times (7-8 AM) correspond to very early morning HST (2-3 AM), and late morning EST (10 AM-12 PM) corresponds to early morning HST (5-7 AM). Late afternoon EST (3-5 PM) aligns well with late morning/midday HST (10 AM-12 PM), making this an ideal window for winter business coordination.
How does winter (EST) coordination differ from summer (EDT) coordination with Hawaii?
During winter (November-March, EST season), the East Coast is 5 hours ahead of Hawaii, providing limited overlap for business hours. During summer (March-November, EDT season), the difference increases to 6 hours, making the time gap even larger. Many businesses adjust their schedules seasonally to accommodate these changes, with winter being slightly more favorable for synchronous communication.
Pro Tips
- • EST is always 5 hours ahead of HST during winter months (November-March).
- • When daylight saving time begins (second Sunday in March), EST becomes EDT and the difference increases to 6 hours.
- • Late morning EST times (10 AM-12 PM) correspond to early morning HST times (5-7 AM), ideal for coordinating business operations.
- • Hawaii does not observe daylight saving time, so HST is consistent year-round while EST changes once per season.
- • For long-term projects spanning both seasons, account for the time difference change when EST transitions to EDT in March.
- • Late afternoon EST (3-5 PM) aligns well with late morning/midday HST (10 AM-12 PM), providing excellent overlap for winter business calls and coordination.
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