Forex What indicator is best for gaging the volatility of a swing?

Some swings in prices are more volatile and sharper than others, which includes a sudden reversal, compared to a swing where price 'crawls' away from the low or high with less volatility. So, although you can use your eyes to try and see this, is there an indicator which can help deceiver which swings are more volatile than others when comparing them in a more black and white sense.

Many thanks.

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