All-time high (ATH)

An all-time high is the highest price an asset has ever traded at. Its counterpart, the all-time low (ATL), is the lowest recorded price. Price trackers usually show how far the current price sits below its ATH as a percentage.

ATH figures depend on the data source and the currency. A coin can hit an all-time high in rupees without doing so in US dollars if the rupee has weakened against the dollar in the meantime. Different aggregators also average different exchanges, so their records can differ slightly.

Distance from the all-time high says nothing on its own about whether an asset is cheap or expensive. Many coins that fell 90% from their peaks never recovered. Treat it as context, not a signal.