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How to track a competitor’s prices without a subscription

Shopify storefronts publish more price data than most merchants realise. Here is how to read it, what to write down each week, and how to tell a real move from noise — without paying for anything.

Last updated 14 September 2026 · about 6 minutes to read

Watch ten items, not a catalogue

The instinct is to track everything a rival sells. Do not. A 200-item price list you check once and abandon is worth less than five items you actually look at every week.

Pick the items where you compete head to head: the products a customer would genuinely buy from either of you. Five to ten is the right number. Those are your watch items, and everything below is about them.

Where the prices live

You do not have to click through product pages one at a time. Most Shopify storefronts publish their catalogue as JSON at a predictable address:

Inside, each variant carries the three fields that matter: price, compare_at_price and available. Between them they tell you the live price, whether it is discounted, and whether you can even buy it.

compare_at_price is the field people miss

When compare_at_price is higher than price, that item is on sale right now — even if nothing on the page says so and no banner is running. It is the most reliable public signal that a competitor has started discounting.

Some merchants disable the JSON endpoint. If it 404s, the product page itself still shows the live price, and the sorted collection view at /collections/all?sort_by=price-ascending gives you their cheapest entry point in one glance.

What to record each week

One row per week. Keep it boring and numeric — the value is in comparing rows, so anything you cannot compare is wasted typing.

ColumnExampleWhat it tells you later
Date2026-09-14The interval a change happened in
Price per watch item39.00The headline number you are tracking
Compare-at price48.00Whether that price is a markdown or their new normal
AvailablefalseSold out is an opportunity, and it explains odd price moves
Banner text“20% off site-wide”The campaign the price change belongs to

Telling a real move from noise

Not every changed number deserves your afternoon. A workable filter:

Answering a price cut without giving up margin

The reflex is to match. It is usually the worst available option, because it hands your pricing decision to a competitor who may be clearing stock, testing, or simply wrong.

What this free method cannot do

Being straight about it: the manual version has real limits, and they are not solved by trying harder.

Common questions

Can I track competitor prices in Google Sheets?

Sheets has no native JSON import, so the realistic free version is a manual weekly log: one row per week, one column per watched item. That is fine, because the right number of items to watch is five to ten, not your rival's whole catalogue.

How big a price change is worth reacting to?

As a rule of thumb, ignore anything under about 5 percent on a single item: that is usually rounding, a currency conversion or a variant-level tweak. React to changes on your head-to-head bestsellers, to a new compare-at price that signals a campaign, and to anything that crosses a psychological threshold like $50.

Should I just match their price?

Usually not. Matching a price you did not choose hands your margin to someone else's decision. Answer it instead: bundle, improve the shipping or returns promise, or lean on the thing they cannot copy this week. Match only when the item is a genuine commodity and price is the only reason anyone buys it from you.

Is scraping a competitor's prices allowed?

Reading public product pages is ordinary competitive research. If you automate it, respect robots.txt, keep the request rate low and stay off anything behind a login. Promolexa's own checker honours robots.txt, which is why it sometimes declines to read a store.

See a rival’s current prices free

Paste a store address and get its live price range, product count and whatever promos are running right now. No install, no account.

Promolexa takes the weekly reading for you, emails you only when something moved, and drafts the response in your brand voice. Free plan available · Standard $29/month with a 7-day free trial.