Time & Dates
Time difference between the zones
The gap between the two clocks is the difference of the offsets. A positive value means the source zone is ahead, which is the gap to quote for a call or a meeting.
The Formula
difference = source offset - target offset
The gap between the two clocks is the difference of the offsets. A positive value means the source zone is ahead, which is the gap to quote for a call or a meeting.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| o_s | Source offset | hours | Hours the source zone is ahead of UTC. |
| o_t | Target offset | hours | Hours the target zone is ahead of UTC. |
| Δ | Difference | hours | How far ahead the source zone is. |
What Each Symbol Means
o_shours
Source offset
Hours the source zone is ahead of UTC.
o_thours
Target offset
Hours the target zone is ahead of UTC.
Δhours
Difference
How far ahead the source zone is.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to convert time zones page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Convert Time Zones, filed under Everyday Life. Every number the guide produces comes from substituting into this one line.