What is Share of Search — and why does it predict sales?

Most marketing metrics tell you what already happened. Share of Search is unusual because it tells you what is about to happen — and it does it using data anybody can pull for free.

The basic idea

Share of Search is simple arithmetic. Take every branded search query in your category over a period. Work out what proportion of them were for you. That percentage is your Share of Search.

If buyers in your category ran 100,000 brand searches last month and 12,000 of them were for you, your Share of Search is 12%.

Why it predicts sales

The finding that made this metric famous belongs to Les Binet, who tested it against the UK car, energy and mobile markets. In each, Share of Search moved before market share did — leading it by roughly six to twelve months, with the longer leads in the categories that have the longer purchase cycles.(Binet, Share of Search, 2020–21)

The mechanism is not mysterious. Searching for a brand by name is an act of intent. Nobody types a brand into Google idly — they do it because they are considering it. So a rise in branded search is a rise in the number of people who have moved you onto their shortlist. Those people convert later, which is why the sales number follows.

What makes it genuinely useful

• It is free. Google Trends gives you a relative version at no cost.
• It is fast. Monthly, not quarterly, and with no panel lag.
• It is competitive by construction. A share metric moves when rivals move, so it catches a competitor's momentum that your own sales figures would hide until it was too late.
• It survives budget arguments. It is the closest thing brand marketing has to a leading number the finance team will accept.

The three traps

Google Trends is relative, not absolute. Trends normalises everything to a 0–100 index, which means a small but fast-growing brand can look flat next to an incumbent. For a directional read it is fine. For a number you will put in a board pack, you need absolute search volumes.

Google is not the whole category. A meaningful and growing share of product discovery now starts on TikTok, YouTube, Amazon or an AI assistant. A Google-only Share of Search is a real number about an increasingly partial picture.

It only counts people who already know your name. This is the big one, and it is the reason the metric has a blind spot.

The number Share of Search cannot give you

Share of Search counts branded queries. By definition, it can only see buyers who already know you exist.

But roughly 54% of Google searches never mention a brand at all(Ahrefs, 332M queries). Those are the questions — best sunscreen for oily skin, is it worth the money, what do dermatologists recommend. The people asking them have not shortlisted anyone yet. They are deciding who to shortlist, right now, based on whoever answers.

Share of Search cannot see any of them. It picks the story up one step later — after somebody else's answer has already put a name in the buyer's head.

That is the gap Answerz Share measures: of all the unbranded questions your buyers ask before they buy, what proportion do you actually come back as the answer to? Share of Search is the outcome. Answerz Share is the input that moves it.

How to use both

Run them together and they answer different questions:

• Share of Search falling? Demand for your name is softening. Usually a brand-building problem, and usually visible before sales confirm it.
• Answerz Share low? You are absent from the conversations that create demand in the first place. Fix this and Share of Search should follow — that is the causal direction.
• Answerz Share up but Share of Search flat? Your answers are being published but not found. Amplification problem, not a content problem.

The pairing matters because acting on Share of Search alone tends to push brands toward more advertising to people who already know them. The cheaper win is usually the 54% who are asking a question right now and have not heard of anybody yet.