Bound Data Staleness in a Polling Workflow

How to Use This Tool

Separate polling interval from network, processing and clock-delay assumptions. Estimate average and worst-case API polling staleness from interval, request latency, processing delay and allowed clock skew.

The decision this tool supports

Calling an endpoint every minute does not mean data is one minute fresh when transport, local processing and timestamp skew are added afterward. This page keeps the decision bounded to worst-case modeled staleness and the supporting outputs shown beside it. Polling Staleness does not import an account, infer a market rate, or silently substitute an industry average.

Inputs and units

The Polling Staleness calculation uses Polling interval, Request and response latency, Local processing delay, Allowed clock skew. Keep all money values in one currency and all time, distance, mass, energy or volume entries in the unit printed beside the field. Mixing Polling Staleness scopes can produce a plausible number with the wrong meaning.

• Polling interval is entered in seconds.
• Request and response latency is entered in seconds.
• Local processing delay is entered in seconds.
• Allowed clock skew is entered in seconds.

Formula and worked check

Worst-case staleness = poll interval + round-trip latency + processing delay + clock skew; average assumes a uniform change time and uses half the interval. A 60-second interval plus two seconds latency, three processing and one clock skew gives 66 seconds worst case and 36 seconds average. The Polling Staleness default is an executable known-answer case, not a benchmark or recommendation. Change one input and verify that the direction of worst-case modeled staleness still matches the stated relationship.

How to interpret the result

Use worst case for freshness commitments and average only for capacity tradeoffs when changes are plausibly uniform within intervals. The additional Polling Staleness outputs expose the denominator, comparison, capacity or reverse value needed to audit the primary result instead of presenting one unexplained number.

Assumptions

• A successful poll completes every interval.
• Changes are uniformly distributed for the average case.
• All entered delays are upper bounds for the same workflow.

Save the Polling Staleness input values and date with any material decision. A later Polling Staleness rerun is reproducible only when the same assumptions and units are available.

Limitations and safety boundary

It excludes server-side source lag, retries, rate limits, missed polls, caching, queueing, clock-step events and nonuniform change timing. Polling Staleness is an estimate and cannot replace a contract, local code, licensed professional, calibrated measurement, lender statement or platform report where one governs the decision.

Source and privacy

The Polling Staleness definition or rule was checked against OpenAPI Specification on 2026-08-26. Recheck OpenAPI Specification when a specification or policy behind Polling Staleness can change. Polling Staleness arithmetic runs in this browser tab; ecech does not receive the values through a calculation API.