Coinbase limits for your account will always be displayed on the Account Limits tab of your account settings.
Your remaining weekly limits will also be displayed on the right-hand side of the page when you go to buy or sell cryptocurrency and may change depending on the payment method (for buys) or withdrawal type (for sells).
For daily limits, this is the amount you can spend in a 24-hour period. For weekly limits, this is the amount you can spend in a 7-day period.