Ananthika Sanilkumar was born on February 2, 2006, in Thrissur, Kerala, to Sanilkumar and Jini Sanilkumar. A trained classical dancer proficient in Bharatanatyam, Mohiniyattam, Kuchipudi, and Kathakali, she is also a black belt holder in karate with training in Kalaripayattu and sword-fighting, and is currently pursuing a BA LLB alongside her acting career.

She made her acting debut in 2022 with the Telugu film Rajahmundry Rose Milk, followed by MAD (2023), where she played a young woman navigating a schizophrenia diagnosis. At 18, she became one of Rajinikanth's youngest co-stars, playing Dhanalakshmi in Lal Salaam (2024), and went on to star in 8 Vasantalu (2025). She next appears in Romanchakam, a romantic comedy-thriller from Sandeep Reddy Vanga's production banner, alongside Sumanth Prabhas.