Evaluation how AI video generators handle our test prompts, which you can learn more about below, is a major part of how we decide which apps make this list. Furthermore, all of the entries here are full-service AI video generation apps that work without additional configuration, meaning you can just download them or open their web pages to get started. You can also generate AI videos locally on your computer with a powerful enough setup (such as with Stable Diffusion), but those solutions are outside the scope of this list.
Although we tailor our testing to each app and its unique features, such as ChatGPT's Storyboard feature in Sora or Gemini's Flow feature in Veo, our evaluation encompasses four primary pillars: audio, basic scenes, complex motion, and text. We use the exact same prompt to get the clips in the cards above for the sake of a fair comparison.
When we test the audio component of AI videos, we aren't analyzing waveforms or measuring bitrates. Rather, if a particular app supports audio generation, we listen closely to see if the sound matches up with what's happening on-screen. Oftentimes, AI-generated videos with audio lack certain sound effects or include effects that don't make sense. If the audio matches what's in the frame, we look to see if it syncs up perfectly, since effects often fire just a moment too soon or late.
Particularly with AI voices, we listen for any distortion or obvious processing. Although it can be somewhat challenging to describe in words, AI voices often have a noticeably robotic quality. A good point of comparison for AI voices is Sesame, a Technical Excellence 2025 award winner; its AI voices sound conversational and exceptionally realistic.
AI-generated videos can sometimes be quite realistic, but you often have to pay for a service, run multiple generations, and carefully tweak your prompt to prevent them from looking or sounding fake. However, the technology is rapidly improving. Soon, it will likely be difficult to tell the difference between an AI video and a real one, even if you use a free app and an unsophisticated prompt.
Sometimes, though, this is increasingly common. For example, whereas ChatGPT's Sora 1 and Gemini's Veo 2 AI video generation models didn't generate audio, Sora 2 and Veo 3 do. If you want an AI video with accompanying audio, check if the app you plan to use supports it before refining your prompts.
Some AI video generation models are free to use, but the answer isn't always straightforward, even within the context of a single app. For example, ChatGPT initially limited its original Sora model to paid subscribers but made Sora 2 available for free, albeit on an invitation-only basis. If you don't want to pay for AI video generation capabilities, expect significantly fewer features and restrictive usage limits.
Yes, but this limit varies depending on the app. The AI video generation apps we tested don't support videos longer than 25 seconds, which is itself a limitation, as it is only possible with an expensive ChatGPT Pro subscription. That said, some apps help you work around these limitations. For example, Gemini's Flow tool in Veo lets you extend AI-generated clips, while Adobe Firefly helps you generate a video based on the last frame of another video you provide.
The short answer is that you can't always tell. A variety of signs can help you determine if a video is likely authentic, but the tell-tale characteristics of AI videos might become increasingly difficult to spot as the technology improves.
Prompt engineering is the practice of designing and optimizing requests to an AI to get the best possible results, and this is a key component of AI video generation. Even changing just a few words in a prompt can have a significant impact. Generating something multiple times, even with the same prompt, can also get you different results. Check out our guide on getting the most out of AI video generation for some advice on making the best videos possible.
Yes, but there are some caveats. Not every app allows this, and those that do usually have restrictions. ChatGPT's Sora, for example, features a Cameo system that enables you to generate AI-generated videos of yourself or others that share their likeness. Many historical figures are fair game, too. That said, OpenAI banned the use of Martin Luther King Jr.'s likeness, as well as that of living celebrities (outside of those who set up Cameos).
Grok's Imagine AI video generator generates explicit content if requested, but most mainstream AI video models don't. This feature is more common in the world of NSFW AI chatbots. Grok's NSFW AI content isn't particularly impressive, so I suggest using a dedicated service if you're looking for NSFW AI content.