Gamma AI Slide turns a topic, your notes or a web page into a slide deck. It researches, asks a few questions, lets you edit the outline, then builds the slides. When you add your own files, every number traces back to them, and anything they don't say is marked TBD instead of made up. Export editable PPTX or PDF, or upload an old .pptx to rewrite or translate its text in place. 20 free credits with Google sign-in, one-time packs, no subscription.