Time to reach 100 million users: LinkedIn: 7 yrs, 11 months Pinterest: 5 yrs, 6 months Twitter: 5 yrs, 2 months Facebook: 4 yrs, 7 months YouTube: 4 yrs, 1 month WhatsApp: 3 yrs, 4 months Instagram: 2 yrs, 4 months TikTok: 9 months ChatGPT: 2 months