What is Purchase Intent?

Purchase intent is a respondent's self-reported likelihood of buying, typically captured after exposure to a concept, price, or product description, with a question such as "How likely would you be to purchase this?" and a scale like definitely would, probably would, might or might not, probably would not, definitely would not. Researchers usually report top-box (share choosing "definitely would") and top-two-box (definitely plus probably) figures, and compare them across concepts, segments, prices, and against category norms. The measure is a staple of concept testing and market research because it is fast, cheap, and comparable; its weakness is that it is a statement about a future the respondent controls only in principle.

Stated Intent Versus Behavior

Decades of comparisons between stated intent and subsequent purchase show a consistent pattern: intent predicts behavior directionally (concepts with higher intent generally sell better) and overstates it in absolute terms, with the gap largest for new products, expensive purchases, and socially desirable choices. Most people who say they "definitely would buy" don't, and a meaningful share of buyers came from the "might or might not" group. The reasons are the standard hypothetical-bias mechanisms: no money is at stake, the concept is presented in its best light, respondents want to be helpful, and real purchase involves competitors, budgets, and timing the survey removed. The measure is therefore a relative instrument first (which concept, which segment, which price) and an absolute forecast only after calibration.

Calibration Conventions

Consumer research developed rules of thumb for converting stated intent into expected trial: weighting each scale point by a fraction (a large discount on "definitely", a heavier one on "probably", near zero below), calibrated against historical launches in the category. The specific weights vary by category, price point, and market, and any team using them should treat published multipliers as illustrative and build their own from whatever purchase data exists. Without calibration, top-two-box percentages should be reported as comparative scores, never as forecast demand.

Measuring It Well

1. Show the concept as the buyer would meet it.
Real price, realistic presentation, competitors named where they'd be present; intent for a concept described without a price measures interest, not intent. Presenting the concept on screen and capturing a recorded reaction before the intent question (a Ballpark concept study runs exactly this sequence) also captures the why.

2. Use the standard scale and report top-box and top-two-box.
Comparability with category norms and with your own past studies depends on a fixed instrument.

3. Ask the buyer, not the user.
In B2B, intent from the person who doesn't hold the budget measures enthusiasm; the audience is the decision-maker.

4. Add a reason and a barrier question.
"What would stop you?" after a low-intent answer is where the actionable content lives.

5. Pair with revealed-preference evidence where the decision is expensive.
Pre-orders, deposits, waitlist conversion, a priced landing page test, or a conjoint study that forces trade-offs: anything that costs the respondent something moves the estimate toward the truth, the same escalation described under willingness to pay.

The Bottom Line

Purchase intent is a fast, comparable measure of stated buying likelihood that overstates real purchase in predictable ways. Present the concept realistically, keep the scale fixed, ask the buyer, report top-box comparisons rather than raw forecasts, calibrate against real purchase data before predicting demand, and escalate to methods where money is involved when the decision is worth it. Intent tells you which concept and which segment; only spending tells you how many.