Babies typically start to sit up on their own between 7 to 9 months of age. Some may begin sitting with support as early as 4 to 6 months, but independent sitting usually develops a bit later as they gain the necessary back, neck, and core strength. Around 6 months, many babies can sit with support or in a tripod position using their hands for balance. By 7 to 9 months, most babies can sit steadily without support, which marks a significant milestone in their mobility and exploration abilities. Each baby develops at their own pace, so some might sit up earlier or later within this range.