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How to Measure Saltwater Fish

Most finfish size limit regulations of the Florida Fish and Wildlife Conservation Commission (FWC) use either Fork Length or Total Length.

These measurement methods provide a consistent, well defined measurement technique. These methods encourage angler compliance with fishery management regulations.

For more information please visit the Fish Length Measurement FAQs.
Watch a Public Service Announcement about Measuring Fish. (wmv 1MB)

Total Length Measurement

Total Length is now measured from the most forward point of the head, with the mouth closed, to the farthest tip of the tail with the tail compressed or squeezed, while the fish is lying on its side.

Red Drum fish

Mutton Snapper fish

Yellowmouth Grouper

Total Length Species Include:
Snapper Family	Tripletail
Grouper Family	Bonefish
Red Drum	Sheepshead
Black Drum	Flounder
Snook	Several ornamentals
Spotted Seatrout	(Angelfish, etc.)
Weakfish
Click here for a more detailed list

Fork Length Measurement

Fish regulated by fork length are measured from the tip of the jaw or tip of the snout with closed mouth to the center of the fork in the tail.

Spanish Mackerel fish

Hogfish

Gray Trigger Fish

Fork Length Species Include:
Amberjacks	Bluefish
Rudderfish	King Mackerel
Hogfish	Spanish Mackerel
Dolphin	Permit
Cobia	Pompano
Mullet	African Pompano
Gray Triggerfish

Lower Jaw Fork Length Measurement (Billfishes)

Fish regulated by lower jaw fork length are measured in a straight line from the anterior most part of the lower jaw (tip of the lower jaw) to the fork in the tail.

Lower Jaw Fork Length Species Include:

Sailfish
Blue Marlin
White Marlin

How to Measure Stone Crab and Spiny Lobster

Stone Crab Measurement

Stone Crab claws must measure at least 2 3/4-inches in length measured by a straight line from the elbow to the tip of the lower immovable finger. The forearm (propodus) shall be deemed to be the largest section of the claw assembly that has both a moveable and immovable finger and is located farthest from the body of the crab.

Stone Crab Measurement

Spiny Lobster Measurement

Spiny Lobster must have a minimum carapace length of greater than 3-inches and the measurement must take place in the water. The carapace is measured beginning at the forward edge between the rostral horns, excluding and soft tissue, and proceeding along the middle to the rear edge of the carapace.

Lobster measurement