Share of Voice for Local Businesses: Google + Mentions + AI in One View

Ask a marketer what "share of voice" means and most will describe the advertising version: your ad spend divided by total category ad spend. Most local businesses don't buy enough media for that number to mean anything. But the underlying idea — how much of the conversation about your category you actually own, compared to the businesses you're competing with — still applies. It just has to be measured across the places that conversation is actually happening now: organic search, independent mentions, and AI answers. This is a guide to the combined version, not the AI-only version. If you specifically want to go deep on how AI assistants describe you versus competitors, Tailwind's AI Visibility tool tracks exactly that slice on its own. This article is about putting all three channels — search, mentions, AI — on one dashboard, because checking them one at a time is where most businesses get misled. The classic formula, and why it travels The standard share of voice formula is simple: Share of Voice = (Your Metric ÷ Total Market Metric) × 100 In advertising, "your metric" is ad spend and "total market metric" is total category spend. If you spend $10,000 a month on local ads and your five visible competitors collectively spend $40,000, your share of voice is 20%. The formula travels well to other metrics because it's really just a ratio: your piece of a measurable pie, divided by the whole pie. That's why it also works for search visibility (your keyword rankings vs. competitors' rankings, across the terms that matter), for mention volume (how often you're named across a set of sources vs. how often competitors are), and for AI-answer share (how often an AI assistant recommends you vs. how often it recommends each competitor, across a set of realistic questions). The math is the same ratio each time — what changes is what you're counting. Why one channel's number lies to you Here's the problem with stopping at one channel: each one measures a different kind of attention, and they don't move together. A business can rank well in Google's local pack — strong reviews, solid on-page SEO, consistent NAP data — and still be functionally invisible when someone asks ChatGPT or Gemini "best [category] near [city]." AI assistants don't just re-rank Google's results; they synthesize an answer from a different mix of signals, weighted toward whichever reviews, descriptions, and third-party mentions happen to be well-structured and specific enough to quote. A business with five generic five-star reviews ("Great service!") can lose that comparison to a competitor with three detailed reviews mentioning exact services and neighborhoods, even if the five-star business outranks them on Google. The reverse happens too. A business can get genuinely strong independent attention — a popular Reddit thread, a mention on a local subreddit, a Hacker News discussion if the category fits — and have that attention contribute nothing to its Google ranking or its AI visibility, because nobody built the connection between "people are talking about us here" and "our website/profile reflects that." Independent mentions are a real signal of market presence, but only if something downstream (a review, a link, a citation) turns the mention into something Google or an AI assistant can actually find and weigh. Checking only one channel means you only see one slice of a three-part picture, and the slice you check is rarely the one that's actually weak. How to estimate your share, channel by channel You don't need enterprise tools to get a rough, directionally useful number for each channel. Here's the practical version of each calculation. Search visibility share Pick the 10–15 search terms a real customer would actually use — not just your business category alone, but the category plus your city or neighborhood, plus a handful of "near me" and comparison phrasings. For each term, record whether you appear in the local pack (and at what position) and whether you appear in organic results below it. Do the same for your 5–10 closest competitors. Your rough share of voice for search is: the number of top-3 local-pack appearances you have, divided by the total top-3 appearances across you and your tracked competitors combined, across all the terms you checked. It's not a perfectly scientific metric — Google's local pack shifts by query, by time of day, and by the searcher's exact location — but run consistently across the same term list every month, it tells you whether you're gaining or losing ground. Mention share Count how many times you and each tracked competitor are mentioned across the sources that matter for your category — local subreddits, niche forums, "best of" roundup posts, local news coverage, and (where relevant) sites like Hacker News for more tech-adjacent local businesses. A simple site-restricted search (`site:reddit.com "your business name"` and the same for competitors) over a fixed period, say the last 90 days, gives you a usable count. Your mention share is your count divided by the total mentions across everyone you're tracking. This number is noisier than search share — a single viral thread can swing it hard in either direction — so treat spikes as worth investigating, not as a new steady state. AI-answer share Ask each major assistant — Claude, ChatGPT, Gemini, Copilot, Perplexity — the same handful of realistic, non-branded questions ("best [category] in [city]," "who should I use for [service] near [neighborhood]") multiple times each, since answers aren't always identical run to run. Record whether you're named, where, and whether competitors are named instead. Your AI-answer share is the fraction of those runs where you show up, relative to the total times anyone from your tracked set shows up. This is the channel most businesses have never checked even once, and it's also the one changing fastest — assistants update their blended web/training data regularly, so a number from six months ago tells you very little about today. Putting the three together Once you have a rough share for each channel, the useful exercise isn't averaging them into one score — it's looking at where they disagree. Strong on search, weak on AI answers, is a specific, fixable gap (usually: your content and reviews aren't specific enough for an AI assistant to quote confidently). Strong on mentions, weak everywhere else, means your independent attention isn't being converted into anything a search engine or assistant can act on. Weak across all three against one specific competitor is the clearest signal of all — it tells you exactly who to study. Tailwind's Brand Visibility report runs this comparison for you automatically — pulling search visibility, independent mentions, and AI-answer checks into one cross-channel share of voice report against the local competitors you actually compete with, instead of three separate numbers you have to reconcile by hand. Start with the gap, not the average The point of measuring share of voice across channels isn't to produce one tidy percentage. It's to find the specific channel where you're losing ground without knowing it — because that's the one costing you customers right now. Get your free Brand Visibility report and see where you actually stand against the competitors in your city, across search, mentions, and AI, in one view.