Purpose and scope
What this dashboard measures
Measure clock drift, parts per million, and projected daily error.
Reference start, Reference end, Device start, and Device end feed the component values beneath the Clock Drift and Skew Calculator headline; Carry Device end in its entered unit for comparison.
Instructions
How to use this calculator
Supply Reference start and Reference end from the Clock Drift and Skew Calculator planning source, then carry Device start and Device end in their recorded units.
- Supply Reference start and Reference end from one Clock Drift and Skew Calculator reporting period.
- Supply Device start and Device end without changing the Device end unit.
- Calculate the Clock Drift and Skew Calculator and match its headline with component values.
Interpretation
Interpreting the headline metric
The projected daily error assumes linear drift and no clock correction.
Audit Reference start, Reference end, and Device start beside the Clock Drift and Skew Calculator headline; Device end reveals rounding across the component values.
For a separate check, the Log Timestamp Normalizer and Sorter is designed to normalize mixed-zone log entries to UTC and sort them chronologically.
Calculation
Method used
Device elapsed time is compared with reference elapsed time to calculate skew, drift rate, and projected daily error.
The Clock Drift and Skew Calculator evaluates Reference start, Reference end, and Device start separately; carry Device end visible outside any percentage, rate, or total.
Calculation method last reviewed: June 21, 2026.
Worked scenario
Example calculation
Match Device end with the Clock Drift and Skew Calculator component values before judging the Device end headline scale or units.
Visual audit
Reading the supporting metrics
The Clock Drift and Skew Calculator dashboard places component values beside Reference start, Reference end, Device start, and Device end. Audit Device end in its original unit before accepting the component values or headline status.
Boundaries
Important edge cases and limitations
Oscillator temperature, step corrections, leap handling, sampling error, and nonlinear drift are excluded.
Adjust Device end in the Clock Drift and Skew Calculator before reading the component values or headline.
Input audit
Checklist for this calculation
- Audit the Clock Drift and Skew Calculator period and Reference start and Reference end units.
- Match Device end with the Clock Drift and Skew Calculator component values.
- Calculate a fresh Clock Drift and Skew Calculator after any Device end adjust.
Practical use
Recommended workflow
Measure over a representative interval and separate oscillator drift from NTP steps or manual adjustments.
Move from the Clock Drift and Skew Calculator to the NTP Timestamp Converter when the goal is to convert between UTC time and the NTP seconds epoch.
Questions
Frequently asked questions
What does positive drift mean?
The device clock accumulated more elapsed time than the reference and is running fast over the measurement.
How does Device end qualify the clock drift and skew calculator headline?
The Clock Drift and Skew Calculator headline compresses Reference start and Reference end, so match it with Device end and component values. The Device end denominator then exposes rounding in the Clock Drift and Skew Calculator.
What context prevents a saved clock drift and skew calculator result from becoming ambiguous?
A reproducible Clock Drift and Skew Calculator record includes Reference start and Reference end, Device start and Device end, their units, and the date on which the output was generated.