Decide what sort of boot you've got. is the only incredibly flexible, semi-flexible or rigid? Does it have toe or heel welts, or each? When you have particularly bendy boots without toe welts, you could want a brand new boot in case you are making plans to put on them with technical mountain climbing crampons.
What activities are you planning? For mountain climbing or mountain climbing, examine the toe and heel of your boot. You've got several crampon binding options. For taking walks in preference to climbing, take into account less-technical crampons with a strap-on binding. If you need step-in crampons, hold in mind you want stiff-soled boots with thick welts or grooves on the toe and heel.
Suit the flexibility of your shoes with the ability of the crampon. For highly bendy boots, get crampons with a flexible middle bar that connects the back and front. you could put on aluminum crampons with sneakers (and strap-on bindings) for mild mountaineering or glacier tour, just make sure the power is comparable.
Carry along your boots while buying. This is a clever way to make sure a crampon suits. make sure the middle bar fits the boot for flex, form and length. Climbers regularly make micro-adjustments, like adjusting the toe bail, to comfortable a continuing suit.
While in doubt, go with a strap-on device. This suits most footwear fine, and it is always higher to errors at the aspect of getting a crampon that fits!