Based on the information available and my own knowledge, the best free AI image generator available appears to be DALLE-2 by OpenAI. DALLE-2 is known for its ability to create detailed and lifelike images from text prompts, making it a popular choice among creative professionals. The interface is easy to use and the results are often impressive. However, it's worth noting that there are other AI image generators available, such as DreamStudio by Stability AI and Visme's text-to-image generation tool, which may offer different features and customization options depending on your specific needs. It's always a good idea to try out a few different options to see which one works best for you.