Stop size mistakes before they become returns.
FITLD matches each shopper's measurements to the size chart of the exact product they're looking at, selects the right size on your page, and shows you on every order whether it was the right call.
Free to start. A Shopify app, or one script on any website. Always free for shoppers.
Shopping for yourself or your family? Create a free profile
Men / T-shirts
Essential Cotton Tee
$34.00
Midweight cotton, regular fit. Taxes included.
Size
Choose a size
Free shipping and 30-day returns
The store only gets the size, never the measurements.
From size chart to the right size in four steps
No new checkout, no app for shoppers to install. FITLD sits next to your own size selector.
Add your size charts
Start from a standard chart, import the size guide you already have, or fill in our Excel template. Each product keeps its own chart and fit: slim, regular, oversized.
Put the button on your store
On Shopify, install the FITLD app and switch it on in your theme, no code. On any other website, paste one script. Both are shown below.
Shoppers get their size
They enter a few measurements once, for themselves or anyone in their family, and FITLD selects the right size in your size picker. When no size fits, it says so.
See what happened
Results show how many shoppers got a size and which sizes they kept. On Shopify, their orders and refunds show up too.
On Shopify
The FITLD appNo code, about 5 minutes
- Install FITLD Size Finder from the Shopify App Store.
- Switch the button on under App embeds in your theme editor, and save.
- Give your products a size chart in the app. Orders and refunds connect by themselves.
Your plan goes on your Shopify bill.
Or the script
- Paste the FITLD script in layout/theme.liquid, just before </body>.
- Add the two order notifications in Settings, Notifications to see orders and refunds.
Your plan is billed on fitld.com.
On any other website
- Paste the script on your product pages: WooCommerce, Wix, Squarespace, BigCommerce, Magento, PrestaShop or your own site.
- FITLD adds the button under your size picker, or put your own button exactly where you want it.
- The confirmed size is selected in your picker, with an event your developer can listen to.
Your plan is billed on fitld.com. Order tracking is Shopify-only for now.
Shopify and the Shopify bag logo are trademarks of Shopify Inc. FITLD is an independent app.
See how it works, with screens · Read the full install guide or try it on a sample product.
Everything people wear, for everyone in the family
Each category asks only for the measurements it needs — a belt needs a waist, a watch needs a wrist.
Clothing
- Tops
- Bottoms
- Dresses & jumpsuits
- Outerwear
- Activewear
- Underwear & sleepwear
- Swimwear
Footwear
- Sneakers
- Formal shoes
- Boots
- Sandals & slides
- Sports shoes
- Socks & hosiery
Accessories
- Watches & bracelets
- Belts
- Hats
- Gloves
- Neckwear
- Adults
- Body measurements — chest, waist, hips, feet and more, only what the product needs.
- Kids & toddlers
- Height first, age to break ties — including toddler sizes like 2T–5T.
- Babies
- Age in months. No tape measure needed.
Know whether it worked, order by order
Most size tools tell you how often they were opened. FITLD connects to your Shopify orders and refunds, so you see what actually happened after the recommendation.
- Size match. How often shoppers bought the size FITLD recommended.
- Refunds, compared. Refund rate for shoppers who used FITLD versus those who didn't.
- Charts that need fixing. Products where shoppers keep choosing a different size than recommended.
- Demand by size Coming soon Which sizes shoppers need, to plan stock and your next production run.
Last 30 days
Sample data
- Bought the recommended size
- 78%
- Orders after using FITLD
- 236
Refund rate
For shoppers: measure once, for the whole family
Save your measurements in a free FITLD profile, add your kids, and get the right size on every store that uses FITLD.
Private by design
Stores receive the size, never your measurements.
Family profiles
Add your partner and kids by name, then switch between them in one tap.
Help as you measure
Every measurement comes with a short how-to.
Free, always
No ads, no subscription, no data sold.
- Create a free FITLD profile
Be one of our first ten pilot brands
We review your size charts for free, set FITLD up on your store with you, and send you a weekly report for 30 days. No card, no commitment.
Questions brands ask
About 5 minutes with the Shopify app: install it, switch it on in your theme and give your products a size chart. With the script, usually under an hour. During the pilot we do the setup with you.
The app, for most stores: no code, orders and refunds connect by themselves, and your plan goes on your Shopify bill. Use the script if you'd rather pay on fitld.com or keep apps off your store. Every plan includes every feature either way.
Yes. The widget runs on any website with one script tag, and there's a REST API for apps and headless stores. Order tracking currently connects to Shopify; other platforms are on the way.
The script loads asynchronously, after your page content, so it never blocks your product page from showing.
Only the recommended size and anonymous usage counts. Shoppers' body measurements stay in their own FITLD profile and are never shared with brands.
FITLD only asks shoppers for measurements the chart actually uses, and if a chart can't support a confident answer it says so instead of guessing. When a shopper is outside every size, FITLD tells them no size fits rather than picking the nearest. Your dashboard shows which products need better charts.
Always. Shoppers never pay, see ads, or have their data sold.