Denver
Riyadh
Convert MST to AST
Mountain Standard Time to Arabia Standard Time — Riyadh is 9 hours ahead of Denver
Quick Facts
Time Difference
+9 hours
MST Full Name
Mountain Standard Time
AST Full Name
Arabia Standard Time
MST to AST Conversion Table
Related Conversions
About MST and AST Time Zones
MST (Mountain Standard Time) is UTC-7 and covers cities like Denver, Phoenix, Salt Lake City. AST (Arabia Standard Time) is UTC+3 and covers cities like Riyadh, Jeddah, Baghdad.
When it's 12:00 PM (noon) in Denver (MST), it's 9:00 PM in Riyadh (AST). The time difference between MST and AST is 9 hours — Riyadh is ahead of Denver.
The 10-hour difference makes real-time overlap challenging — early morning calls (7–9 AM MST) work best.
Daylight Saving Time
MST observes Daylight Saving Time and becomes MDT (Mountain Daylight Time) during summer months, shifting clocks forward by 1 hour to UTC-6.
During DST transitions, the time difference between MST and AST may shift by ±1 hour. Always verify the current offset above for the most accurate conversion.
Use our world clock tool to compare Denver and Riyadh with a visual timeline, or browse more timezone conversions.
Frequently Asked Questions
What is the time difference between MST and AST?
Riyadh (AST) is 9 hours ahead of Denver (MST). The offset is +9 hours.
Is AST ahead or behind MST?
AST is 9 hours ahead of MST. MST is UTC-6 and AST is UTC+3.
When it's 12:00 PM in Denver, what time is it in Riyadh?
When it's 12:00 PM (noon) in Denver (MST), it's 9:00 PM in Riyadh (AST).
When it's 5:00 PM in Denver, what time is it in Riyadh?
When it's 5:00 PM in Denver (MST), it's 2:00 AM in Riyadh (AST).
Does MST change for Daylight Saving Time?
Yes. MST (Mountain Standard Time, UTC-7) becomes MDT (Mountain Daylight Time, UTC-6) in summer, shifting clocks forward 1 hour.