Sketch filters run edge detection on a photo and darken the lines, which gives every picture the same scratchy look. Image to sketch AI draws the picture again the way an artist would: it picks the main shapes, builds shadows with hatching or smudges, and leaves out clutter. A graphite portrait and a charcoal dog come out as different kinds of drawing, not the same effect at two strengths.
People use it for a pencil portrait of a parent, a drawing of their first home, a reference for a tattoo artist or a set of pages for a travel journal. GPT Image 2.5 is the default because it follows long notes about tools and paper. Nano Banana 2 and Nano Banana Pro usually keep faces closest to the photo, and FLUX.2 is free for signed-in accounts and works from a single photo.
New accounts get 8 free credits and 4 more each day from the second day. With GPT Image 2.5, a 1K image costs 3 credits, 2K costs 4 and 4K costs 7, and the cost shows next to the Generate button.
Uploads are used only to make your drawing, and results stay private in My Images until you delete them.