Home-frozen tuna isn't safe to eat raw.

No, I wouldn’t.

The risk is parasites. Commercial “sushi-grade” tuna gets frozen at temperatures your home freezer can’t reach—usually -20°F or colder for at least a week. Most home freezers hover around 0°F. That’s not enough to reliably kill the worms (anisakis, usually). Thawing doesn’t fix it.

I’ve done it. I’ve been fine. But that’s luck, not safety. If you’re set on raw tuna, buy it from a fishmonger who labels it sushi-grade and confirms it’s been blast-frozen. Otherwise, cook it.

Sushi is expensive enough. Don’t cheap out on the fish.