Wrong sizes are a line item
Fit is the top reason apparel comes back. SizeGuide puts the right size on the product page and shows you what that is worth.
A model, not a promise. Every assumption is yours to change.
computed live from the sliders. nothing here is a claim about SizeGuide.
From the charts you already have
No body scans, no data projects, no photo studio. Your size charts exist today; SizeGuide makes them work harder.
Connect your store
Install the Shopify app. Your catalog syncs read-only.
Import charts
CSV, metafields, or a photo. Uncertain cells are flagged for your review before anything publishes.
Map to products
Auto-suggested from your catalog, confirmed by you. Blanks like Gildan and Bella+Canvas are already on file.
Publish
Smart charts on every PDP. Turn on recommendations when you are ready, on the same data.
It will never embarrass your store
It never guesses
Below the confidence floor the engine declines and asks for one more measurement, instead of shipping a wrong size under your brand.
It shows its work
Every recommendation carries the chart row, the shopper's numbers, and the chart's provenance. Shoppers can check it.
It respects your shoppers
Measurements stay with the shopper. You see a size, never a body. Deletion is one click.
Measured, not promised
Sizing tools love to promise conversion lift. SizeGuide measures it on your store, against a control group, from day one.
A/B against control
A holdout share of traffic sees no recommendations, so the lift you read is yours, not an industry average.
Return-risk flags
Products whose fit signals look wrong get flagged, so you fix the chart before the returns arrive.
Size distribution
What was recommended, what was bought, and where they disagree. The disagreements are your merchandising signal.
If the numbers are not there, you will see that too. Honest measurement cuts both ways, and we publish the methodology.
When an AI agent asks
"what size should they buy?"
SizeGuide answers in structured, explainable JSON. Fast enough for conversational checkout, auditable enough to trust.
One conversation, two views: the shopper's chat on the left and the exact API traffic behind it on the right.
Stateless fast path
A single REST call returns the full recommendation. No sessions, no orchestration, edge-served.
MCP server
Native tools for agent ecosystems: recommend_size, convert_size, get_size_chart, explain_fit.
Open sizing schema
A published, versioned JSON standard for charts and fit responses. Free to adopt, built to be cited.
Charts are free. The full chart manager is $29. Recommendations are $99.
See it on your products
Send us one product page. We return it running SizeGuide on your real chart: provenance label, live unit conversion, recommendation and all. Your garments, your charts, your reality.
Request your pageMerchant questions, answered directly
How long does setup actually take?
Minutes for a typical store: install, import, map, publish. Photo and PDF charts add a review step where you confirm flagged cells. Printing on standard blanks is faster still, because those charts are already in the database.
Will this increase my conversion rate?
We do not promise a number, because honest tools cannot. We measure your lift against a control group on your own traffic and show you the result, whichever way it goes.
What do my shoppers actually see?
A clean size chart with a provenance label on every product page, and, on Growth, a size recommendation with confidence, reasoning, and an honest decline when we cannot be sure.
Do you collect my shoppers' body data?
Shoppers can enter measurements to get a recommendation, and those measurements belong to them, not to you and not to advertisers. Your store receives a size. Shoppers can delete their data in one click.
Which platforms do you support?
Shopify first, with a one-line embed for any other storefront and a REST API underneath everything. The same engine answers on every surface, so nothing ever disagrees.