Choose the right size boots

Measure your horse's hooves and compare the measurements to the chart.

Take the measurements a day or two after the hooves have been trimmed, and make sure to measure all four feet, as they may differ in size.

Flex boot measuring guide how to measure
Flex Hoof Boot size chart.PNG

For advice regarding the best boot size for your horse, please contact us or your nearest retailer.

Please note that if your horse's hooves are at the maximum width and length measurements for a specific size, the boot might not fit well and sizing up might be necessary.

For example, if your horse's hoof is 155mm wide and 160mm long (maximum measurements for size 150 boot), then the boot might not fit well. However, if the hoof is slightly narrower at 150mm wide and still 160mm long, it will fit the boot well, as long as the heels are trimmed to the correct position. Flex Hoof Boots work better if they are slightly loose rather than if they are too tight, as loose boots' fit can be improved with Flex Pads. 


Measure after a trim

This is when the hooves are at the correct size and shape.


Hooves should be maintenance trimmed weekly, to retain the shape and balance of the hoof.


Imagine drawing a line across the back of the hoof, from heel to heel. From the middle of that line draw another line straight to the toe. This is where you measure the length of the hoof.

Heel buttress

When measuring the length of the hoof, do not measure the heel buttress, only the weight-bearing area of the hoof wall.


Measure the width at the widest part across the hoof.

Size post-trim

If after a fresh trim the hoof is for example 115mm wide and 120mm long, we recommend size 120 with Flex Pads to accommodate slight hoof growth between trims.

Growth speed

If the last trim was, say 3 weeks ago, and the hoof measurements are the same as right after the trim (115mm wide, 120mm long), then  size 110 would be best, as long as you trim frequently enough to stop the hooves expanding.

Hoof shape

Flex Boots suit many different shape and size hooves. However, if the hoof width is over 10mm greater than the length, our boots are not ideal for your horse.


If the hoof is very narrow and the horse has a habit of twisting its legs a lot, it may be that our flexible boot is not suitable for your horse.

Need help with Flex Boot fitting?

We offer free fitting advice via email to help you determine the best boot size for your horse. For accurate guidance, please email us photos of your horse's hooves. We will need a front, sole, side and sole side view photos, as shown here. Ideally these photos should be taken within a day or two of a trim.

If you have purchased Flex Boots and are having issues with the fit, in addition to the hoof photos, please also send us clear side view photos of the hooves with the boots on.

Our email for fitting advice is 

Flex Boot fitting advice hoof photos.jpg

Please note that we may use your photos for educational purposes on our website, blog and social media channels. All client photos will be used anonymously, and we never share any confidential information about you or your horse. If you would prefer us not to use your photos, please notify us of this, and we will be happy to oblige.

Fitting and adjusting the Flex Boots

Once you have chosen the right size boots for your horse, fitting them correctly is important for the comfort of your horse and longevity of the boots.  That's why we have written extensive instructions to help you achieve the best fit for your horse. Click on the images below to read more, or download our printable fitting instructions document.