Is Superman More Powerful Than Supergirl? Fans Keep Joking About Superman’s ‘Real’ Plot, And It Made Me Dive Down A Rabbit Hole

Though we’ve known for years that the DC Universe’s Supergirl is getting her own, Milly Alcock made a surprise cameo as the Girl of Steel this past summer in the 2025 movie release of Superman. Our brief moment spent with her teased that Kara Zor-El has a harder edge than her cousin Kal-El/Clark Kent, which we’ll see the full extent of when Supergirl flies onto the 2026 movies schedule. But is Superman actually more powerful than Superman, or is it the other way around? That’s a question I looked into after falling down a rabbit hole on social media.

Now Superman's available to stream with an HBO Max subscription, I stumbled across an Instagram post where people were joking that the “real” plot of the movie is how Clark was actually trying to save Lex Luthor’s life by rescuing Krypto before Kara found out, since it turned out that was her dog. That would indicate that Kara would have no trouble beating Lex within an inch of his life, if not kill him, which Clark would definitely not condone.

I then noticed some people in the comments saying how Supergirl is more powerful than Superman, which puzzled me. So, I dove down a rabbit hole.

What's The Deal? Is Superman More Powerful Than Supergirl?

Listen, I’ve read a fair number of Superman comics and watched many Superman-related movies and TV shows over the years. In all that time, I’ve never seen anything to indicate that (generally speaking) Supergirl is stronger than Superman, although that can obviously change depending on the continuity, alternate timeline stores, etc.

So, I did a little research, and as far as powers go, Kara and Kal do indeed have the exact same set because of their Kryptonian physiology, from super strength and flight to heat vision and cold breath.

However, there are other factors to consider. For one thing, Superman has lived on Earth since he was an infant, while Supergirl only arrived here as a teenager. So Clark has been soaking up radiation from Earth’s yellow sun for a lot longer and has had most of his life to get a handle on these abilities.

Conversely, Supergirl is trained in martial arts, both from her adolescence on Krytpon to what she’s learned on Earth from fellow superheroes like Batman and Wonder Woman. Also, there have been times when Kara has been more driven by rage than Kal, to the point where she was once bonded with a Red Lantern ring. So if we’re dealing with a Supergirl who’s less restrained with using her powers, that would give her an added advantage in battle compared to Superman, who would hold back -- so as not to kill anyone.

One More Thing Worth Noting About James Gunn's DCU.

When it comes to the DCU, we have no idea yet if Supergirl is more powerful than Superman. Just because she’s a party girl doesn’t mean she’ll extremely violent in her upcoming DC movie, although I do buy that she would have treated Lex Luthor with a rougher hand if she’d learned what happened to Krypto.

Ultimately, it just depends on the circumstances. Still, for now, I’m working under the assumption that Superman has a better handle on his powers because of how long he’s been on Earth.

But hey, maybe I’ll be proven wrong when Supergirl is released in theaters on June 30, 2026. For now, Peacemaker Season 2 is keeping the DCU chugging along on HBO Max, and Lanterns will follow on HBO sometime in early 2026.