A familiar annual date is not a substitute for understanding how a measurement system is used. The interval needs a basis relevant to the application.
NIST's calibration-interval guidance does not prescribe one universal interval for every measuring instrument. NIST — Recommended calibration interval.
Review the relevant factors
For a production measuring device, consider applicable requirements, use conditions and available performance history with the responsible specialist. Keep the interval decision separate from a supplier's convenient service calendar.

Revisit when conditions change
A changed use or concerning observation may justify review before the planned date. Follow the applicable measurement-control process rather than assuming the calendar alone establishes continuing suitability. Record the reason for the selected interval and subsequent changes.

Source reviewed 25 October 2026. Interpretation and original diagrams: PLUSHIP / Qunhe. Examples are illustrative.
Related reading
Metrological Traceability Belongs to a Measurement Result
Calibration, Adjustment and Verification Describe Different Work
Displayed Resolution Is Not the Complete Measurement Uncertainty
