top of page
![2020 LOGO [Recovered]-10_edited.png](https://static.wixstatic.com/media/9fa7b1_9c72bb33d58648358f55fe749b613b75~mv2.png/v1/fill/w_134,h_21,al_c,q_85,usm_0.66_1.00_0.01,enc_avif,quality_auto/2020%20LOGO%20%5BRecovered%5D-10_edited.png){kind=small}
ABOUT
Measuring Guide
“Designed to Hug, Not Hold”
Unlike cookie-cutter chairs, the Testa-Seat is shaped to follow the body’s flow. Its curved shell creates a snug, cozy fit — more like a gentle hug than a rigid seat — so kids feel secure wherever they are.
Fit Comes First
Accurate sizing isn’t just a step — it’s what makes the Testa-Seat feel like it was made for your child. The right fit means more comfort for meals, play, and everyday moments.
Like Shoes,
It’s All About the Fit
We’ve got three Shell sizes — built to grow with kids from about 1 to 8 years old.*
Before You Click Buy
Like shoes, size matters. You can measure at home or work with a professional to make sure you get it just right.
Right size = right fit.
*Please note: Age ranges are just a guide — every kid grows on their own schedule.
Measurement Guide
-
Units - Choose cm or inches and stick with it for every field.
-
Seat your child comfortably - Have them sit upright on a firm, flat surface with hips, knees and ankles at 90°.
-
Measure in straight lines - A rigid ruler or calipers work best. Hold the tool close to clothing (no bulky layers).
➡️ Write down the exact number — don’t add extra "for growth.”
-
Type your numbers into the chart — it will instantly show how they line up with each Testa-Seat size.
📏 Seat Dimensions - The tick marks under the ruler indicate the internal dimensions of each seat size.
How each dimension relates to the seat
1+2 Seat & Chest Width (Most Important).
Green tick mark = internal width of each seat size.
Red vertical line = hard limit of the seat.
How to read the 🟥 Attention markers:
Pointer left of red line → good support.
Pointer on the red line → seat will be tight with good snug support.
Right of red line → seat will be too narrow. Choose the next size up or custom.
3+4 Side Height & Seat Depth
Green tick mark = actual seat dimension of each size.
Orange horizontal line = that 2.5 cm threshold.
How to read the 🟧 Attention markers:
Measure left of orange line → armpit/knee will hit the rim during use. The orange line shows the range which the child can fit. But for the best comfort, we recommend choosing a size that is at least 2.5 cm (1 inch) larger than the seat’s actual dimensions (Greater then the orange line).
5 Back Height
Closer match = more contact. Higher = still supportive. Lower = less back contact, but still usable.
1 Seat Width
Distance between outer hips
3 Side Height
Seat to underside of armpit
2 Chest Width
Full chest width
4 Seat Depth
Seat to back of knee
5 Back Height
Seat to base of neck
bottom of page