Todd Flanders is voiced by Nancy Cartwright, Aurelia Bruno in French and Dani Chauveau in Canadian French. Todd is the youngest and most impressionable member of the happy Flanders flock. When exposed to profanity (for example, in the episode, Bart the Lover, from over the fence as Homer Simpson curses his way through mowing the lawn), little Todd starts to curse a blue streak himself ("Hell, no." and "I said I don't want any damn vegetables). When Moe Syzlak loses his temper at Uncle Moe's Family Feedbag restaurant, Todd responds with "Ow, my freaking ears!" Whether due to immaturity or relentless sheltering by his parents, whenever Todd comes into contact with anything outside of his family and their pious ways (like the time he was tricked into eating a Pixie Stick by Bart Simpson), he turns nasty, for example calling his brother a "zitface", .

Todd's proudest moments have been when he tied with Bart in the mini-golf championship and when he portrayed Jesus in the Springfield Christmas Pageant. Todd can play the violin quite well, and is a part of the Springfield Elementary band. He is also prone to bedwetting. Todd's voice is based on Sherman's from Peabody and Sherman.