Examples
Examples
Try the starting example
- One-way distance to supplied turnaround point (km)
- 5
- Supplied outbound speed (km/hour)
- 3
- Supplied return speed (km/hour)
- 4
- Supplied latest return timestamp
- 2026-10-20T18:00
- Outbound start timestamp
- 2026-10-20T09:00
- Return-deadline buffer minutes
- 30
- Break at turnaround, whole minutes
- 15
- Latest modeled arrival at turnaround before break
- 2026-10-20T16:00
- Modeled outbound arrival at stated speed
- 2026-10-20T10:40
- Modeled return timestamp after turnaround break
- 2026-10-20T12:10
- Latest-turnaround arrival minus modeled arrival (minutes)
- 320
- Modeled return walking minutes, rounded upward
- 75
Try another scenario
- One-way distance to supplied turnaround point (km)
- 5
- Supplied outbound speed (km/hour)
- 3
- Supplied return speed (km/hour)
- 2
- Supplied latest return timestamp
- 2026-10-20T18:00
- Outbound start timestamp
- 2026-10-20T09:00
- Return-deadline buffer minutes
- 30
- Break at turnaround, whole minutes
- 15
- Latest modeled arrival at turnaround before break
- 2026-10-20T14:45
- Modeled outbound arrival at stated speed
- 2026-10-20T10:40
- Modeled return timestamp after turnaround break
- 2026-10-20T13:25
- Latest-turnaround arrival minus modeled arrival (minutes)
- 245
- Modeled return walking minutes, rounded upward
- 150
Calculation method
Calculation method
Latest modeled arrival at turnaround before break
Latest return−buffer−rounded return walk−turnaround break.
Modeled outbound arrival at stated speed
Start+ceil(distance/outbound speed×60).
Modeled return timestamp after turnaround break
Outbound arrival+break+rounded return walk.
Latest-turnaround arrival minus modeled arrival (minutes)
Signed scenario slack; negative means the supplied plan misses its modeled turnaround constraint.
Modeled return walking minutes, rounded upward
Ceil(distance/return speed×60), using exact supplied decimal fractions.
Symbols and units
- a
- One-way distance to supplied turnaround point (km)
- b
- Supplied outbound speed (km/hour)
- c
- Supplied return speed (km/hour)
- d
- Supplied latest return timestamp
- e
- Outbound start timestamp
- f
- Return-deadline buffer minutes
- g
- Break at turnaround, whole minutes
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- A constant supplied-speed return-deadline scenario for one stated point, not an actual safe turnaround recommendation. Conditions, navigation, fatigue, terrain and emergency response are outside the model.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.
Further reading
OpenStax: ratios and rates; all itinerary rates, limits and scenario rules are supplied inputs ↗
Background reading; this does not imply endorsement or independent review of SumFizz.