The forearm is long, gently tapered and mostly flat on the outside, which makes it a natural home for vertical designs: an animal portrait, a koi, a dagger, a long botanical stem. The inner forearm faces you, so it suits words you want to read yourself. Designs that wrap around the arm, like a mountain band or a coiling snake, read from every angle and move well as you turn your wrist.
Forearm skin holds ink well and ages more gracefully than hands or fingers. The main enemy is sun: the forearm is out in the light whenever your sleeves are up, and UV light fades ink over time. Sunscreen on healed work keeps blacks dark and colors bright for longer. Fine-line pieces hold better here than on hands, though very small lettering still softens with the years.
A forearm tattoo is visible in short sleeves and when you roll your shirt up, but a long sleeve covers it completely. Many workplaces that frown on hand or neck tattoos are fine with forearms, though it is still worth checking a dress code first. That flexibility is why so many people start a sleeve here.
Healing is usually easy because you can see and reach the whole area. Keep tight cuffs and watch straps off it while it heals, and expect some extra tenderness near the wrist and the elbow crease, where the skin moves the most.