Ice Thickness Chart: How Thick Ice Should Be to Walk, Fish or Drive

This guide is for anyone planning to walk, ice fish, skate or ride on a frozen lake or pond this winter.

Ice can look solid and still be dangerous. A thickness chart is a starting point, not a guarantee, and you have to measure the ice yourself.

The quick answer

The Minnesota Department of Natural Resources (DNR) says there is no such thing as 100 percent safe ice.² Its guidelines for new, clear ice say to stay off ice under 4 inches, and that 4 inches is enough for ice fishing or other activities on foot.¹

The ice thickness chart

The Minnesota DNR’s guidelines for new, clear ice only:¹

White ice and old ice need more

The DNR says to double the thickness guidelines on white ice, because white ice is only about half as strong as new, clear ice.¹ It also warns that while 4 inches of clear, newly formed ice may support one person on foot, a foot or more of old, partially thawed ice may not.²

Measure it yourself

The DNR says it does not measure ice thickness on lakes and that your safety is your responsibility.¹

Our advice:

• Check thickness with an ice chisel, auger or drill as you go, not just at the shore.
• Watch for slush, cracks, dark spots, and ice near inlets, outlets, docks and moving water, which is often thinner.
• Don’t go out alone, and tell someone where you’ll be.
• Carry ice picks around your neck and a rope, and wear a life jacket or float coat.

Checklist

• Under 4 inches of clear ice: stay off.
• Double the numbers for white ice.
• Measure often as you go out.
• Never go alone.
• Remember: no ice is 100 percent safe.