HST to EDT Converter
Convert time between Hawaii Standard Time (HST) and Eastern Daylight Time (EDT)
Hawaii Standard Time (HST)
Eastern Daylight Time (EDT)
Time Difference
Eastern Daylight Time (EDT) is 0 hours ahead of Hawaii Standard Time (HST)
Select Date
Select Time
Quick Reference
| HST | EDT |
|---|---|
| 16:00 | 21:00 |
| 18:00 | 23:00 |
| 20:00 | 01:00 |
| 22:00 | 03:00 |
| 00:00 | 05:00 |
| 02:00 | 07:00 |
| 04:00 | 09:00 |
| 06:00 | 11:00 |
| 08:00 | 13:00 |
| 10:00 | 15:00 |
| 12:00 | 17:00 |
| 14:00 | 19:00 |
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 HST to EDT Time Conversion
Converting time between Hawaii Standard Time (HST) and Eastern Daylight Time (EDT) is important for coordinating between Hawaii and the US East Coast during daylight saving time. HST is UTC-10, while EDT is UTC-4, making EDT 6 hours ahead of HST. Hawaii does not observe daylight saving time, but the East Coast does, adding complexity to the conversion.
This conversion is vital for business operations, tourism coordination, and personal communications between Hawaii and the East Coast. Understanding this significant time difference is crucial for scheduling meetings, managing customer service, and coordinating travel between these distant regions, especially during the March-November daylight saving period.
Common Use Cases for HST to EDT Conversion
Business & Work
- Scheduling calls with East Coast offices from Hawaii headquarters during daylight saving time
- Coordinating customer service operations across US time zones
- Managing tourism and hospitality reservations from East Coast
Personal & Travel
- Scheduling video calls with family and friends on the East Coast
- Planning travel from Hawaii to the East Coast
- Coordinating vacation and holiday time across time zones during spring and summer months
Time Zone Information
Hawaii Standard Time (HST)
- UTC Offset: UTC-10
- IANA Timezone: Pacific/Honolulu
- Daylight Saving: No daylight saving time observed
- Major Cities: Honolulu, Hilo, Maui, Kauai, Big Island
- Coverage: State of Hawaii
Eastern Daylight Time (EDT)
- UTC Offset: UTC-4 (UTC-5 during EST)
- IANA Timezone: America/New_York
- Daylight Saving: Second Sunday in March to First Sunday in November
- Major Cities: New York, Boston, Atlanta, Miami, Philadelphia, Washington DC
- Coverage: Eastern United States and Canada
Quick Reference: HST to EDT
Remember: EDT is always 6 hours ahead of HST during daylight saving time (March-November). Outside this period, EST is 10 hours ahead of HST
Frequently Asked Questions
What is the time difference between HST and EDT?
Hawaii Standard Time (HST) is UTC-10, while Eastern Daylight Time (EDT) is UTC-4. EDT is 6 hours ahead of HST. This means when it's 8:00 AM in HST, it's 2:00 PM the same day in EDT.
Does Hawaii observe daylight saving time?
No, Hawaii does not observe daylight saving time. Hawaii Standard Time (HST) remains UTC-10 year-round. However, the Eastern region observes daylight saving time, transitioning from EST (UTC-5) to EDT (UTC-4). This means the time difference varies between 5 hours (when EST is active, November-March) and 6 hours (when EDT is active, March-November).
How does HST to EDT differ from HST to EST?
EDT (Eastern Daylight Time) is 1 hour ahead of EST (Eastern Standard Time). When EDT is active (March-November), the difference between HST and EDT is 6 hours. When EST is active (November-March), the difference between HST and EST is 5 hours. EDT is used during daylight saving time on the East Coast.
What major cities are in HST and EDT timezones?
HST covers Hawaii cities including Honolulu, Hilo, Maui, Kauai, and the Big Island. EDT covers major East Coast cities like New York, Boston, Washington DC, Miami, Philadelphia, and Toronto. These regions represent Hawaii and the American East Coast during daylight saving time (March-November).
How do I convert HST to EDT manually?
To convert from HST to EDT, add 6 hours to the HST time. For example, if it's 9:00 AM HST, it would be 3:00 PM EDT the same day. Remember this conversion is only valid during daylight saving time (March-November). When EST is active (November-March), add only 5 hours instead.
What should I know about scheduling across HST and EDT?
Hawaii is 6 hours behind the East Coast during EDT, making coordination challenging but possible. Morning EDT times (9-11 AM) correspond to early morning HST times (3-5 AM), and late afternoon EDT (3-5 PM) corresponds to morning HST (9-11 AM). For regular business coordination, early morning EDT calls (7-9 AM) work well with Hawaii (1-3 AM HST for early risers, or 1-3 PM HST for afternoon workers).
Pro Tips
- • EDT is always 6 hours ahead of HST during daylight saving time (March-November). Outside this period, EST is 5 hours ahead.
- • Hawaii does not observe daylight saving time, so HST is consistent year-round while EDT changes twice annually.
- • Morning EDT (9-11 AM) aligns well with early morning HST (3-5 AM) for early risers or with afternoon HST (3-5 PM) for evening workers.
- • Early morning EDT calls (7-9 AM) work for Hawaii afternoon schedules (1-3 PM HST), allowing both regions to coordinate during business-friendly hours.
- • Use 24-hour time format when communicating across HST-EDT to eliminate AM/PM confusion, especially around morning/evening transitions.
- • Technology, finance, and media businesses between Hawaii and the East Coast often use asynchronous communication due to the significant time difference.