THE NUMBERS, EXPLAINED
How to use this calculator.
Event and arrival timestamps use synchronized clocks and the same origin. Lateness is arrival minus event time; this measures transport delay, not ordering inversions.
Start with your inputs
Enter event timestamps (seconds), arrival timestamps (seconds), chosen lateness buffer (seconds). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Event timestamps (seconds) | 0,10,20 |
| Arrival timestamps (seconds) | 2,15,21 |
| Chosen lateness buffer (seconds) | 3 |
A worked example
With the example inputs above, observed event lateness (seconds) is 2, 5, 1. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Observed event lateness (seconds) | 2, 5, 1 |
| Mean lateness (seconds) | 2.666667 |
| Events beyond chosen buffer (count) | 1 |
| Buffer covering all observed arrivals (seconds) | 5 |
How this is calculated
Observed event lateness (seconds)
Subtract event time from arrival time.
Mean lateness (seconds)
Average observed lateness.
Events beyond chosen buffer (count)
Count strict lateness exceedances.
Buffer covering all observed arrivals (seconds)
Use the maximum observed lateness; this gives no guarantee for future arrivals.
Symbols and units
- a
- Event timestamps (seconds)
- b
- Arrival timestamps (seconds)
- c
- Chosen lateness buffer (seconds)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Event and arrival timestamps use synchronized clocks and the same origin. Lateness is arrival minus event time; this measures transport delay, not ordering inversions.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Observed event lateness (seconds); Mean lateness (seconds); Events beyond chosen buffer (count); Buffer covering all observed arrivals (seconds). The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Event and arrival timestamps use synchronized clocks and the same origin. Lateness is arrival minus event time; this measures transport delay, not ordering inversions.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
Apache Flink Event Time and Watermarks ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
Read the quality report →