Can platies live with swordtails?

Verdict
Yes

Yes. Platies and swordtails get along in the same tank. Both are fine at 72–79°F. Plan on at least 30 gal.

PlatyPlaty70–80°F · pH 7–8.2 SwordtailSwordtail72–79°F · pH 7–8.3

Why it works

Water side by side

55°60°65°70°75°80°85°90°Both: 72–79°Platy 70–80°Swordtail 72–79°
The green band is the temperature range both can live in.
456789Both: 7–8.2Platy 7–8.2Swordtail 7–8.3
The green band is the pH both tolerate.

Size to scale

Platy · 2.5 inSwordtail · 5 in0"1"2"3"4"5"6"
Adult length in an aquarium. A fish can swallow anything that fits in its mouth, roughly a third to half its own length for predators.

Care at a glance

PlatySwordtail
Temperature70–80 °F72–79 °F
pH7–8.27–8.3
Adult size2.5 in5.0 in
Minimum tank10 gal30 gal
TemperamentPeacefulSemi-aggressive
Swims atMiddleMiddle
GroupGroups of 3+Groups of 3+
DietOmnivoreOmnivore

Better tank mates for platies

All platy tank mates

Better tank mates for swordtails

All swordtail tank mates

Questions

Can platies live with swordtails?

Yes. Platies and swordtails get along in the same tank. Both are fine at 72–79°F. Plan on at least 30 gal.

What temperature suits both platies and swordtails?

72–79 °F. Platies need 70–80 °F, swordtails need 72–79 °F.

What size tank do platies and swordtails need together?

At least 30 gal, set by the swordtail. Add space for each extra fish.