Youth sizes are children's shirt sizes: a youth medium is size 10/12 and fits a 28-30 inch chest in Port & Company PC54Y youth, while a youth XL is size 18/20 and fits 32-34 inches.
Method: compiled 2026-09-29 from 7 sources, each named beside its row: Port & Company PC54Y youth spec sheet (https://www.sanmar.com/p/3986_Purple/specSheetMeasurements, fetched live 2026-09-29); Bella+Canvas youth chart (https://www.bellacanvas.com/fit-size-charts, fetched live 2026-09-29); Gildan 8800B youth polo spec sheet (https://www.sanmar.com/p/5323_Royal/specSheetMeasurements, fetched live 2026-09-29); Gildan 5000B youth spec sheet (https://www.sanmar.com/p/439_Daisy/specSheetMeasurements, fetched live 2026-09-29); our page https://theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide (read 2026-09-29); Gildan 5000 spec sheet (https://www.sanmar.com/p/625_Black/specSheetMeasurements, fetched live 2026-09-29); Port & Company PC54 spec sheet (https://www.sanmar.com/p/3985_AquaticBl/specSheetMeasurements, fetched live 2026-09-29). Where a source gives inches only, cm is converted at 2.54 cm per inch and rounded to the nearest cm. Values a source publishes outside a plausible garment range are left out.
What numbers go with youth sizes?
Each youth letter size has a number pair printed on the spec sheet.
| Size | Brand and style | Numeric size | Source |
|---|---|---|---|
| Youth XS | Port & Company PC54Y youth | 4/5 | www.sanmar.com/p/3986_Purple/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth S | Bella+Canvas youth | 6/8 | bellacanvas.com/fit-size-charts, "Youth" row, fetched 2026-09-29 |
| Youth S | Gildan 8800B youth polo | 6/8 | www.sanmar.com/p/5323_Royal/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth S | Port & Company PC54Y youth | 6/8 | www.sanmar.com/p/3986_Purple/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth M | Bella+Canvas youth | 10/12 | bellacanvas.com/fit-size-charts, "Youth" row, fetched 2026-09-29 |
| Youth M | Gildan 8800B youth polo | 10/12 | www.sanmar.com/p/5323_Royal/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth M | Port & Company PC54Y youth | 10/12 | www.sanmar.com/p/3986_Purple/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth L | Bella+Canvas youth | 14/16 | bellacanvas.com/fit-size-charts, "Youth" row, fetched 2026-09-29 |
| Youth L | Gildan 8800B youth polo | 14/16 | www.sanmar.com/p/5323_Royal/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth L | Port & Company PC54Y youth | 14/16 | www.sanmar.com/p/3986_Purple/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth XL | Bella+Canvas youth | 18/20 | bellacanvas.com/fit-size-charts, "Youth" row, fetched 2026-09-29 |
| Youth XL | Gildan 8800B youth polo | 18/20 | www.sanmar.com/p/5323_Royal/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
| Youth XL | Port & Company PC54Y youth | 18/20 | www.sanmar.com/p/3986_Purple/specSheetMeasurements, 'Size' row, fetched 2026-09-29 |
What chest does each youth size fit?
Body chest by brand, measured around the child.
| Size | Brand and style | Measurement | Inches | cm | Source |
|---|---|---|---|---|---|
| Youth XS | Gildan 5000B youth | Body chest it fits | 21-22.25 | 53-57 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Size Chart 'Chest Width' row, fetched 2026-09-29 |
| Youth XS | Port & Company PC54Y youth | Body chest it fits | 22-24 | 56-61 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Size Chart 'Chest' row, fetched 2026-09-29 |
| Youth XS | Bella+Canvas | Body chest it fits | 22-24 | 56-61 (as published) | theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide, table "Bella+Canvas Youth Size Chart", row "YXS", read 2026-09-29 |
| Youth S | Gildan 5000B youth | Body chest it fits | 23.75-27 | 60-69 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Size Chart 'Chest Width' row, fetched 2026-09-29 |
| Youth S | Port & Company PC54Y youth | Body chest it fits | 25-27 | 64-69 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Size Chart 'Chest' row, fetched 2026-09-29 |
| Youth S | Bella+Canvas | Body chest it fits | 26-28 | 66-71 (as published) | theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide, table "Bella+Canvas Youth Size Chart", row "YS", read 2026-09-29 |
| Youth M | Gildan 5000B youth | Body chest it fits | 27.5-28.5 | 70-72 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Size Chart 'Chest Width' row, fetched 2026-09-29 |
| Youth M | Port & Company PC54Y youth | Body chest it fits | 28-30 | 71-76 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Size Chart 'Chest' row, fetched 2026-09-29 |
| Youth M | Bella+Canvas | Body chest it fits | 28-30 | 71-76 (as published) | theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide, table "Bella+Canvas Youth Size Chart", row "YM", read 2026-09-29 |
| Youth L | Gildan 5000B youth | Body chest it fits | 30.5-32 | 77-81 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Size Chart 'Chest Width' row, fetched 2026-09-29 |
| Youth L | Port & Company PC54Y youth | Body chest it fits | 30-32 | 76-81 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Size Chart 'Chest' row, fetched 2026-09-29 |
| Youth L | Bella+Canvas | Body chest it fits | 30-32 | 76-81 (as published) | theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide, table "Bella+Canvas Youth Size Chart", row "YL", read 2026-09-29 |
| Youth XL | Gildan 5000B youth | Body chest it fits | 33.5-35 | 85-89 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Size Chart 'Chest Width' row, fetched 2026-09-29 |
| Youth XL | Port & Company PC54Y youth | Body chest it fits | 32-34 | 81-86 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Size Chart 'Chest' row, fetched 2026-09-29 |
| Youth XL | Bella+Canvas | Body chest it fits | 32-34 | 81-86 (as published) | theloyalbrand.com/blogs/blog/bella-canvas-youth-sizing-guide, table "Bella+Canvas Youth Size Chart", row "YXL", read 2026-09-29 |
How does a youth XL compare with an adult small?
Laid-flat chest width on the shirt itself.
| Size | Brand and style | Measurement | Inches | cm | Source |
|---|---|---|---|---|---|
| Youth XL | Gildan 5000B youth | Chest, laid flat | 20 | 51 (converted) | www.sanmar.com/p/439_Daisy/specSheetMeasurements, Product Measurements 'Chest' row, fetched 2026-09-29 |
| Youth XL | Port & Company PC54Y youth | Chest, laid flat | 19 | 48 (converted) | www.sanmar.com/p/3986_Purple/specSheetMeasurements, Product Measurements 'Chest' row, fetched 2026-09-29 |
| Adult S | Gildan 5000 | Chest, laid flat | 18 | 46 (converted) | www.sanmar.com/p/625_Black/specSheetMeasurements, Product Measurements 'Chest' row, fetched 2026-09-29 |
| Adult S | Port & Company PC54 | Chest, laid flat | 18 | 46 (converted) | www.sanmar.com/p/3985_AquaticBl/specSheetMeasurements, Product Measurements 'Chest' row, fetched 2026-09-29 |