How to tell if fish is overcooked

Seafood scares some home chefs — and that’s probably because it’s easy to go from perfect to overcooked very quickly. But there’s no need to be scared of seafood in your kitchen! A little education goes a long way. Ahead, we’re diving into a few simple tricks that will guarantee your fish is cooked, but not overdone.

A common mistake people make when checking to see if their fish is done cooking is to cut a deep slice into the middle of the fish using a knife and then twisting with a fork. While this does allow you to test the flakiness and color of the fish, it can also give the dish a hacked-into, unprofessional look — especially if you check it more than once! We’ve all been there, but there are better ways. 

Trust Your Eyes

Color matters when it comes to fish. Once cooked through, the color will transform from relatively translucent and shiny to opaque and solid. Of course, the actual color will vary based on your choice of fish. For example, salmon goes from deep red to light pink; halibut and cod will go from glossy to solidly white. In addition to color, look closely at the flakiness. If a fish resists flaking when you gently brush a fork along the side, it needs more time cooking. 

The 10-Minute Rule

In order to properly gauge how long you should cook your fish to begin with, try the 10-minute rule. The general go-by is that you should measure the fish’s height at its thickest point (while the cut is laying flat), and then cook it for 10 minutes per inch in length of fish, turning it halfway through the cooking time. If the fish is less than one inch thick, it will need less time — just do a bit of mental math to find your starting point (half-inch pieces should start at four or five minutes, and so on). The trick here is to always test your fish at the minimum cook time mark, so as to avoid overcooking and finding out too late! You can always add cook time, but you can’t take it away.

Reach the Right Temperature

The Food and Drug Administration says that the safest temperature at which to consume salmon is 145 degrees F. Some people prefer their salmon steaks more on the medium side of done, which is about 125 degrees. For halibut, an internal temperature between 120-140 degrees is suitable for a medium to well-done outcome, and cod is best served at 140 degrees. Grab your food-grade thermometer and insert at the thickest part of the fish to get the most accurate reading. 

The Butter Knife Test

If you don’t have a thermometer and don’t mind digging in a bit and risking presentation, the butter knife method will work for you. Insert a butter knife at a 45-degree angle into the thickest part of the fish and hold it there for three full seconds. Then, remove the knife and quickly place the knife tip to your bottom lip. If the knife feels warm, the fish should be done. If it’s still cool, you need to cook a bit longer. Just remember to be gentle with your knife so that the fish doesn’t flake apart!

Ready to put your cooking to the test?

SHOP FISH

One of our favorite reasons to cook fish is that it's fast. Really fast. Depending on how thick it's been cut, a fish filet could bake, broil, poach, grill, or sauté in as little as four minutes! With speed like that, quick and easy seafood recipes are an awesome choice for busy weeknights. The only downfall to that speedy cooking time is how quickly you could accidentally overcook fish. If you haven't had the misfortune of biting into overcooked rubbery fish, consider yourself lucky. Thankfully, there are two simple ways to tell when fish is done so you'll only serve up just-right cooked fish.

The two ways to tell your fish is cooked are visual cues that require no special equipment. When fish reaches the proper cooking temperature it will display these cues.

• Opaque color. When you start cooking fish it's rather shiny and translucent. When it's done, the fish will be opaque.

• Flake easily with a fork. When fish is finished cooking, it'll flake apart with a fork (more on that next).

Undercooked fish resists flaking and is translucent. If your fish is undercooked, continue heating it until it's done. But remember, fish cooks fast, so check it often.

Test Kitchen Tip: Check fish at the minimum cooking time to avoid overcooking.

Scott Little

How to Flake Fish with a Fork

This tried-and-true testing technique is easy to master.

• Insert the tines of a fork into the thickest portion of the fish at a 45-degree angle.

• Gently twist the fork and pull up some of the fish. If it flakes easily, without resistance, the fish is done.

At What Temperature Is Fish Done?

While the fork test and opaque color are excellent giveaways that fish is done cooking, the U.S. Food and Drug Administration (FDA) recommends a safe temperature for cooked fish of 145 degrees F. To test this, use an instant-read thermometer.

How to Cook Fish

Now that you know how to tell if fish is cooked, you can put your knowledge to work and actually cook some fish. Get all the info you need on how to bake fish, how to fry fish (including pan-frying), and how to grill fish.

With your newfound knowledge, you can prepare seafood pasta, fish tacos, grilled fish, or any fish dish just right! No matter what seafood dish you're in the mood for, a restaurant-caliber dinner awaits.

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