Three local-time heat strips across the rotating UTC seriesUpdates with every input
Date & Time
Recurring Event Time-Zone Comparison Calculator
Evaluate a rotating recurring meeting across three UTC offsets, count local-time burden outside a preferred working window, and identify whether rotation meaningfully distributes inconvenience.
Region A off-hours occurrences—
Region B off-hours occurrences—
Region C off-hours occurrences—
Total off-hours assignments—
Burden spread between regions—
Most balanced occurrence—
Rotation fairness score—
Rotation status—
Global rotation fairness ribbon
Three local-time heat strips across the rotating UTC series
Each occurrence is colored by local-time burden for every region, making shared convenience, isolated burden, and rotation fairness visible at once.
Occurrence fairness ledger
UTC start and local meeting window for every region
Compare each rotation's UTC time, three local windows, off-hours flags, total burden, and balance score.
| Occurrence | UTC window | Region A local | Region B local | Region C local | Off-hours regions | Balance score | Rotation note |
|---|
Rotation setup
Define fairness as a series, not one convenient meeting
- Set the first UTC meeting time.
- Choose occurrence count and rotation step.
- Enter effective offsets for three regions.
- Define the preferred local working window.
- Include the full meeting duration.
Fairness logic
A rotation is fair only when burden is distributed across the series
One occurrence may be convenient for two regions and difficult for the third.
The fairness score measures spread in off-hours counts, while the heat ribbon still exposes the total amount of burden.
Calculation method
Rotate one UTC series and score each region's local-time burden
Each occurrence shifts by a fixed UTC step. Region local times are normalized modulo 24; a meeting is preferred only when its full duration fits inside the entered local window.
Detailed calculation process and general formulas
u_i=mod(u₀+(i−1)s,24)l_{ir}=mod(u_i+o_r,24)b_{ir}=1(l_{ir}<w_s or l_{ir}+h>w_e)B_r=Σ_i b_{ir}F=100[1−(max B_r−min B_r)/N]Symbols, meanings, and units
- u_i
- UTC start for occurrence iclock hour
- s
- UTC rotation stephours/occurrence
- o_r
- region r UTC offsethours
- b_{ir}
- off-hours burden flag0 or 1
- F
- rotation fairness scorepercent
Global meeting governance
Balance burden without hiding total inconvenience
Equal discomfort is not automatically a good schedule, so spread and total burden are reported separately.
Region A burden
—Occurrences outside A's preferred window.
Region B burden
—Occurrences outside B's preferred window.
Region C burden
—Occurrences outside C's preferred window.
Distribution fairness
—How evenly off-hours assignments are shared.
Decision takeaway: Prefer a rotation with low total burden first, then use the fairness score to distribute the unavoidable remainder.
Rotation checks
Confirm regional time and policy assumptions
- Offsets can change with daylight saving.
- Preferred windows may differ by weekday.
- Meeting duration can cross local midnight.
- Religious and public holidays need a date-specific calendar.
Fairness evidence
Records that support a recurring-time policy
- Participant location roster
- Effective UTC offsets
- Working-hour agreements
- Attendance by local time
- Rotation exception log
Practical applications
Decisions this calculator is designed to support
Global engineering stand-up
Teams in North America, Europe, and Asia rotate a recurring design review.
What the result clarifies: The ribbon shows whether the inconvenience truly moves rather than remaining with one region.
International governance meeting
A committee wants a documented fairness policy across six sessions.
What the result clarifies: Burden counts and balance score make the rotation auditable.
Worked example
Current-input substitution and reconciliation
Model limitations
This fixed-offset model does not query daylight-saving rules, calendars, individual preferences, part-time schedules, or ambiguous local times. The fairness score measures distribution of an entered burden rule, not participant satisfaction.
Recurring Event Time-Zone Comparison Calculator FAQ
What makes an occurrence off-hours?
Its full local meeting interval does not fit inside the preferred window.
Can a high fairness score still be bad?
Yes. Total burden may be high even when evenly distributed.
Why rotate in UTC?
UTC gives one absolute series before local labels are calculated.
Does the model include daylight saving?
No. Enter the effective offsets for the series.