Sexing young guppies?

Hello! I’m sure this is a very common question, but I was hoping someone could help my ID the sexes of my guppies. I rescued a “Noah’s ark” assortment of tons of fish and that included two young guppies. I’ve kept them in a nursery box because they were so small and plan on releasing them into the tank today. They started the same size but one has grown significantly larger than the other.
The tank is at max capacity so I don’t want more fish.. if there’s a possibility of fry, I’ll move a school of tetras into a smaller tank and add a betta to this tank. But I don’t want to do that unless I know I need to. Is there a way to tell their genders?
Thank you for your help!

The one on the right is female, I think the one on the left is female too, judging by body colours, but harder to see the anal fin to be sure. Look at the difference between male and female anal fins (males have a gonopodium) and you'll be able to tell for sure. They look old enough now that if it were a male, you'd see the gonapodium developing by now if it were male.

One will give you mixed messages. Thats the female.
Jk (but not really), looks like @AdoraBelle Dearheart got this one covered

AdoraBelle Dearheart said:

The one on the right is female, I think the one on the left is female too, judging by body colours, but harder to see the anal fin to be sure. Look at the difference between male and female anal fins (males have a gonopodium) and you'll be able to tell for sure. They look old enough now that if it were a male, you'd see the gonapodium developing by now if it were male.
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Thank you so much!! I appreciate your help. I’ll keep my eyes on them as they develop over the next week or so and see if I notice any changes.
I’m so thankful for this forum. I’ve only ever had bettas and tetras and I feel a bit in over my head with this crazy collection!