13Sizer — Size Calculator

Nobody measures a child twice.

The customer takes the measurements once, presses a button, and 13Sizer tells them their size in
your chart. Not a generic table they have to read across with a finger — their size, and what to do
when their measurements fall between two.

You write your charts in the dashboard: the measurements you ask for, and the range each size
covers. One chart per pattern, because leotards, sets and velvet do not size the same way.

Two places, one chart

• Anywhere on your site. Paste [trecesizer chart="leotards"] and a “Calculate my size” button
  appears. It opens the calculator without loading the page again. If the page already has a size
  dropdown, the answer fills it in — on a product that means the variation and the price follow.
  And the button remembers: next visit it reads “Your size: 10 · recalculate”.
• Inside 13Atelier. With the configurator installed, the size step shows the sizes of your chart
  as cards to pick from, and “I don’t know my size” unfolds the calculator underneath. When it
  answers, it selects that size for the customer, who can still choose another. Size and
  measurements both travel to the order, so whoever cuts the pattern has the numbers — and if the
  customer went against the recommendation, the order line carries both sizes.

Neither plugin needs the other. Without 13Atelier the calculator lives on the shortcode; without
13Sizer the configurator keeps its own size picker.

The shortcode

[trecesizer chart="leotards" label="What size is she?" select="#talla"]

• chart — the size chart, by slug, title or id. Required. Name one that does not exist and
  nothing is printed at all: no button, no error.
• label — the button’s wording. Defaults to “Calculate my size”.
• select — a CSS selector for the dropdown to fill in. Left out, WooCommerce’s own variation
  dropdowns are the target.

What it does when the numbers do not agree

Bodies rarely land inside one row of a chart. When the chest says one size and the waist says
another, 13Sizer says so instead of guessing quietly: it gives the closest size, names the runners
up, and tells the customer to write to you. The order line carries a “Check” note so it does not go
to the cutting table unnoticed.

Set up in three steps

1. Create a size chart: the measurements you ask for, and one range per size.
2. Paste the shortcode where the button should be, or assign the chart to a 13Atelier size step.
3. That’s it.