Can Muslims eat rare steak?

What the Quran actually forbids

The Quran forbids blood, but it describes it precisely as blood that pours out:

"Blood spilled out" (dam masfuh) is the blood that gushes from the animal when it is slaughtered. Halal slaughter is designed to let that blood drain away. The small amount that stays inside the muscle afterwards is forgiven by scholarly agreement; nobody is expected to wash or cook every trace of it away. See How is halal meat slaughtered?

The red juice isn't really blood

The pink liquid on your plate is mostly water mixed with myoglobin, a protein that stores oxygen in muscle and turns red. It's the same reason a rare steak looks red inside. So whether you like it rare, medium or well done is a matter of taste, not religion.

The meat still has to be halal

How it's cooked doesn't change the ruling; where it came from does. A well-done steak from a non-halal source is no better than a rare one. At restaurants, ask whether the beef is halal-certified, and remember that grills are sometimes shared with pork or cooked with wine or beer marinades. For shop-bought meat, see Is supermarket meat halal?

Health comes first

Islam also teaches you to avoid harm. Whole cuts of beef cooked rare are generally considered low-risk by food-safety agencies, because bacteria sit mostly on the surface. Minced beef (burgers) and poultry are different: they should be cooked all the way through. If you are pregnant, elderly or have a weak immune system, follow your doctor's advice, which often means avoiding rare meat for a while.

For a wider overview of what's on the menu, see What can Muslims eat?