Higher than most people expect. The IRS receives 1099s from Coinbase, Kraken, and most major exchanges automatically, so they already know you have activity. Audits specifically targeting crypto have increased significantly since 2021. The bigger risk isn't the audit itself though, it's going in without clean records. If you can't show your cost basis per lot, the IRS can assume $0 basis on every sale, meaning 100% of proceeds are taxable gains. Clean records are your best defense regardless of method you use.