Before setup, define what missing means
A blank field can mean the visitor skipped it, does not know the answer or was never shown the question. Those states are not necessarily equivalent. Decide which ones make the estimate unusable. A required quantity may be essential for a numerical result, while an optional comment may add context without changing arithmetic. Use a separate unknown choice where uncertainty should lead to human review rather than forcing the visitor to enter a made-up value.
Configure requirements by consequence
The validation documentation describes required inputs and length or number constraints. These controls help enforce the format you choose; they do not establish whether a visitor’s answer is true. For a hypothetical room estimate, a zero count might legitimately mean no extra rooms, while an unanswered total-room question prevents an estimate. Write the expected behavior for both. An optional extra should also have a clear default, such as not selected, rather than an unexplained empty multiplier.
Explain why a question is mandatory
A short explanation near a required field can reduce uncertainty without adding unnecessary steps. Say that quantity is needed to estimate scope, rather than declaring that all information is mandatory. If a required question involves information the visitor may not have, provide a useful alternative path. Do not promise that skipping a question has no effect unless the model really supports that claim. Required contact information and optional marketing choices should remain distinct in both language and recorded data.
Test the unanswered path deliberately
Try continuing without the answer, with a legitimate zero and with the explicit unknown choice. Verify that each path gives a comprehensible message and does not expose a misleading total. Then check the saved record so the next person can distinguish missing from zero. These are local planning examples; actual merchant behavior must be checked in the implemented form. A green validation state is not proof that the pricing model has all the information it needs.
Sources used for this page
These records support the facts and comparisons above. Merchant-controlled records are labelled so you can separate product claims from independent evidence.
- Input validation options — Merchant documentation · help.involve.me · Merchant-controlled · checked 2026-09-23
- Using calculators — Merchant documentation · help.involve.me · Merchant-controlled · checked 2026-09-23