Click here to learn more about our different fits and how to choose the size that's right for you.
We strive to make all our products true to size. The sizing charts below are general and not garment specific, but hopefully, it will give you some guidance when choosing your size. In instances where you’re perhaps in between two sizes then take a look at our recommendations below.
For further assistance with sizing, contact us here.
If for some reason you are not 100% satisfied with the size you chose, we’ll happily offer an exchange, refund or store credit on any non-sale garments. For more about our refunds and exchange policy, click here.
|
|
XS |
S |
M |
L |
XL |
XXL |
Waist |
Inch |
27 |
28-30 |
32-34 |
36-38 |
40-42 |
44-46+ |
|
cm |
68 - 70 |
71-76 |
81-86 |
91-96 |
101-108 |
111-116+ |
Chest |
Inch |
32-34 |
34-36 |
38-40 |
42-44 |
46-48 |
50+ |
|
cm |
81.5 - 86 |
86-91 |
96-101 |
106-111 |
116-121 |
127+ |
Measurements in cm.
Measurements include ribbed hem.
Sleeve length from pit to hem.
XS |
S |
M |
L |
XL |
XXL | |
Pit to pit |
47.4 |
51.2 |
55 |
58.8 |
62.6 |
66.4 |
Torso Length |
65.9 |
68.5 |
71 |
73.5 |
76.1 |
78.6 |
Sleeve Length |
50.2 |
52.1 |
54 |
55.9 |
57.8 |
59.7 |
Measurements in cm.
Measurements include ribbed hem.
Sleeve length from shoulder to cuff.
XS |
S |
M |
L |
XL |
XXL | |
Pit to pit |
49.4 |
53.2 |
57 |
60.8 |
64.6 |
68.4 |
Torso Length |
68.9 |
71.5 |
74 |
76.5 |
79.1 |
81.6 |
Sleeve Length |
74.2 |
76.1 |
78 |
79.9 |
81.8 |
83.7 |
Outside Leg measurement (including waist band).
S | M | L | XL | XXL | ||
Inside Leg | inch | 29 | 30 | 30.5 | 31 | 31.5 |
cm | 74.5 | 76 | 77 | 78.5 | 80 | |
Outside Leg | inch | 41 | 41.5 | 42 | 42.5 | 43 |
cm | 105 | 106 | 107.5 | 109 | 110 |
Outer leg length measure from top of waist to ankle.
Measurements in cm.
XS | S | M | L | XL | XXL | |
Waist | 58.9 | 64 | 69.1 | 74.2 | 79.2 | 84.3 |
Hips | 68.9 | 74 | 79.1 | 84.2 | 89.2 | 94.3 |
Outer Leg | 90.3 | 93.5 | 96.7 | 99.8 | 103 | 106.2 |
Leg length measurement includes ankle cuff.
XS | S | M | L | XL | XXL | |
Waist | 70.4 | 75.2 | 80 | 84.8 | 85.6 | 94.4 |
Hips | 82.4 | 87.2 | 92 | 96.8 | 101.6 | 106.4 |
Leg Length | 81.6 | 82.3 | 83 | 83.7 | 84.4 | 85.1 |
XS |
S |
M |
L |
XL |
|
Australian |
6-8 |
8-10 |
10-12 |
12-14 |
14-16 |
US |
2-4 |
4-6 |
6-8 |
8-10 |
10-12 |
European |
34-36 |
36-38 |
38- 40 |
40-42 |
42-44 |
The Altitude range is designed to be a tight, but comfortable, fit. If you size up it will give you a little extra room, but it will still hug your body as that’s what this range is designed to do. If you want a looser fit consider the Ultra or Universal range.
XS | S | M | L | XL | XXL | ||
Bust | inch | 30-32 | 32-34 | 34-37 | 37-40 | 40-42 | 42-45 |
cm | 76-82 | 82-88 | 88-94 | 94-100 | 100-107 | 108-114 | |
Waist | inch | 24-26 | 26-28 | 28-30 | 30-32 | 32-35 | 35-38 |
cm | 58-64 | 64-70 | 70-76 | 76-82 | 82-89 | 89-96 | |
Hips | inch | 34-36 | 36–38 | 38-40 | 40-42 | 42-44 | 44-47 |
cm | 84-90 | 90-96 | 96-102 | 102-108 | 108-115 | 115-122 |
These garments are designed true to size, but going up a size in the Ultra will give it a slightly looser fit, whilst remaining sporty. The Universal and Horizon are already designed as a more casual fit.
XS | S | M | L | XL | XXL | ||
Bust | inch | 29.5–32.5 | 32.5–35.5 | 35.5–38 | 38–41 | 41–44.5 | 44.5–48.5 |
cm | 75-82.5 | 82.5-90 | 90-96.5 | 96.5-104 | 104-113 | 113-123 | |
Waist | inch | 23.5–26 | 26–29 | 29–31.5 | 31.5–34.5 | 34.5–38.5 | 38.5–42.5 |
cm | 60-66 | 66-73.5 | 73.5-80 | 80-87.5 | 87.5-94.5 | 97.5-108 | |
Hips | inch | 33–35.5 | 35.5–38.5 | 38.5–41 | 41–44 | 44–47 | 47–50 |
cm | 83.5-90 | 90-97.5 | 97.5-104 | 104 -111.5 | 111.5-119.5 | 119-127 |
Measurements in cm.
Measurements include ribbed hem.
Sleeve length from pit to hem.
XS |
S |
M |
L |
XL |
XXL | |
Pit to pit |
41.4 |
45.2 |
49 |
52.8 |
56.6 |
60.4 |
Torso Length |
60.5 |
63 |
65.5 |
68.1 |
70.6 |
73.2 |
Sleeve Length |
47.9 |
50.5 |
53 |
55.5 |
58.1 |
60.6 |
Measurements in cm.
Measurements include ribbed hem.
Sleeve length from shoulder to cuff.
XS |
S |
M |
L |
XL |
XXL | |
Pit to pit |
44.4 |
48.2 |
52 |
55.8 |
59.6 |
63.4 |
Torso Length |
62.9 |
65.5 |
68 |
70.5 |
73.1 |
75.6 |
Sleeve Length |
68.2 |
70.1 |
72 |
73.9 |
75.8 |
77.7 |
Measurements do not include the ankle cuff.
Please keep in mind the style of these pants is slightly drop crotch.
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL | |
Waist |
72.4 |
77.2 |
82 |
86.8 |
91.6 |
96.4 |
Hip |
98.2 |
104 |
108.8 |
113.6 |
118.4 |
123.2 |
Leg Length |
56.4 | 57.6 | 58.8 | 60 | 61.2 | 62.4 |
Measurements in cm.
Outer Leg Length includes from the top of the waist to the bottom of the pant leg.
XS |
S |
M |
L |
XL |
XXL | |
Waist 1/2 measurement |
34 |
36.5 |
39 |
41.5 |
44 |
46.50 |
Hip 1/2 measurement |
40 |
42.5 |
45 |
47.5 |
50 |
52.5 |
Outer Leg Length |
106.8 | 108 | 109.2 | 110.4 | 111.6 | 112.8 |
Outside leg measurement includes waist band.
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL |
|
Waist |
68.4 |
73.2 |
78 |
82.8 |
87.6 |
92.4 |
Hip |
94.4 |
99.2 |
104 |
108.8 |
112.6 |
118.4 |
Outside Leg |
95.6 |
96.8 |
98 |
99.2 |
100.4 |
101.6 |
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL | |
Waist |
72.4 |
77.2 |
82 |
86.8 |
91.6 |
96.4 |
Hip |
98.2 |
104 |
108.8 |
113.6 |
118.4 |
123.2 |
Leg Length |
60.5 | 63 | 65.5 | 68.1 | 70.6 | 73.2 |
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL | |
Waist |
72.4 |
77.2 |
82 |
86.8 |
91.6 |
96.4 |
Hip |
98.2 |
104 |
108.8 |
113.6 |
118.4 |
123.2 |
Leg Length |
60.5 | 63 | 65.5 | 68.1 | 70.6 | 73.2 |
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL | |
Waist |
72.4 |
77.2 |
82 |
86.8 |
91.6 |
96.4 |
Hip |
98.2 |
104 |
108.8 |
113.6 |
118.4 |
123.2 |
Leg Length |
42.2 | 44.8 | 47.3 | 49.8 | 52.4 | 54.9 |
Measurements in cm.
XS |
S |
M |
L |
XL |
XXL | |
Waist |
72.4 |
77.2 |
82 |
86.8 |
91.6 |
96.4 |
Hip |
98.2 |
104 |
108.8 |
113.6 |
118.4 |
123.2 |
Leg Length |
10.5 | 13 | 15.5 | 18.1 | 20.6 | 23.2 |
All sizes are given in US Sizing
Men's | Women's | |
S | 4 - 6 | 5.5 - 7.5 |
M | 7 - 10 | 8.5 - 11.5 |
L | 11 - 14 | 12 - 15.5 |
Measurement given for bicep width and arm warmer length. Measure around the fullest part of your upper arm in a relaxed position.
Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit.
Approximate measurements only.
Bicep | Arm Warmer Length | |
XS | 27 - 28 cm | 45 cm |
S | 29 - 30 cm | 46.5 cm |
M | 31 - 32 cm | 48 cm |
L | 33 cm + | 49.5 cm |
Hand Length - Measure from the top of your middle finger to the base of the palm.
Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit.
Pace Gloves:
S | 16 cm |
M | 18 cm |
L | 20 cm |
To measure your head circumference, take a sewing measuring tape and wrap around your head so that the measuring tape winds just above the ears, in the middle of your forehead and in the centre back of your head.
Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit. Approximate measurements only.
Head circumference | |
S/M | 50-60 cm |
M/L | 60-70 cm |
For further assistance with sizing, contact us here.
or make 4 interest-free payments of $20.66 fortnightly with More info
We know what you’re thinking: how will a merino Tshirt keep me cool when it’s warm? Well, we’ll tell you! We’ve blended our softest, finest merino, together with a special blend of plant fibre, to come up with a fabric that will keep your core comfortable and cooler for longer when the temperature rises.
The Celsius Tee is part of our Summerino range, and it features our coolest ever fabric, that is naturally breathable, temperature regulating, moisture wicking and odour resistant - and feels ridiculously good next to your skin.
It’s designed to be worn in milder to warm weather, but really the easy fit delivers performance and comfort all year round. Whether you’re pushing hard, doing not much at all, or something in between, go with the io Women's Celsius Tee to feel good no matter how warm it gets outside.
The Celsius Tee has a versatile and relaxed fit, with a drop back hem for extra coverage.
Pair with a Zodiac Crop Top to maximize comfort, style and MicroMerino® performance.
Why you’d buy this: You want something extra lightweight for warmer weather, or you’re more prone to overheating even in cool weather and want the lightest merino thing you can get your hands on. And you want something natural. This one blends merino with plant fibre so it’s still super natural which means almost no microplastic issues when you wash it or landfill when you’ve finished with it.
As with all our clothes, the merino delivers natural temperature regulation, breathability, moisture wicking and odour resistance.
Designed to have a casual, relaxed fit. True to size.
Model wears size small in Black.
Model specs - height 167cm, chest 78cm, waist 63cm, hips 81cm.
Model is 5'8" and wears size small in Dusty Navy, Blush, and Light Grey Marle.
Warm Weather
Hiking
Running
Yoga
Extra lightweight 150gsm
18.5 microns
45% Australian Merino Wool
45% Tencel
10% Nylon
My first IsoMerino purchase and I love it. Super comfy and warm without being hot. I bought this for warmer weather but been using on runs already in September and I'm impressed with the versatility - hoping it will perform just as well on warmer days. Very happy with my purchase and will be on the look out for more.
I am quite fussy about t shits and am loving my new celcius t. It's comfy and stylish and goes with lot of different outfits. And merino!
So glad I bought the Celsius t-shirt! It's awesome! So light and cool feeling. Perfect for the very hot days of summer. I bought my usual size and the fit is perfect. (I size up for the Altitude range.) Thanks io!
Love the tops I purchased cool and comfortable have worn them to gym and bike ride
Great product. And it’s Australian & it’s pure wool!!
Appropriate for casual, work or play. These t-shirts are cool, soft & comfortable for every occasion.