What Size Anchor Do I Need for My Boat?

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Knowing what size anchor to buy for your boat is a responsible way to ensure safety for you and your guests while enjoying water events. However, several factors influence the size and style of the anchor you buy.

Boat Size

For 20 to 30 foot boats weighing 2,000 to 5,000 pounds, consider using a 25-pound anchor. For longer boats, add 10 to 15 pounds to the anchor per foot. You will have to consider the storage capabilities of your boat since some anchors have irregular shapes that make conventional storage difficult.

Weather and Wave Conditions

Anchors fall into three classifications, lunch, working or storm, and each category has a different holding power for the situation. For example, a lunch hook anchor for a 40-foot boat has a holding power of 300 pounds, however in bad conditions, that same 40-footer requires 2,400 pounds of holding power. Each anchor lists its holding power on the label. Know the weather and wave conditions for the duration of your boating trip to prepare for any type of emergency.


Anchors secure the vessel in place by penetrating the soil and using a combination of suction and resistance, or by snagging on the rocks. Depending on the geography of the region, you may need to have different anchors. In sandy, muddy or gravelly terrain, use a fluke anchor, however in rocky regions, use a kedge or navy anchor. Wing anchors are common but tend to break out during changes in the wind or tide.


In addition to size and holding power, you should consider the ease-of-use when setting and resetting the anchor, the quality of the anchor and the anchor chains and cleats.