Khanna is a columnist at "Daily News and Analysis" after hours and "The Times of India". Penguin Random House have announced that Khanna's book "Mrs Funnybones" hit the Nielsen bestseller list at number 2 in its first week of sales. Launched in Mumbai on 18 August 2015, the book reached number 1 on the bestseller chart of Crossword's Kemps Corner store and received praise from readers and press, eventually making Khanna the highest-selling female author in India for that year. Khanna's second book "The Legend of Lakshmi Prasad", a collection of four short stories, launched in November 2016 sold more than copies. Her latest book, "Pyjamas Are Forgiving" (Juggernaut Books, 2018) was released in September 2018 and has made her the highest-selling female author in India in the year 2018, according to Nielsen BookScan India. The publisher reported that the book debuted at number 1 on the Nielsen Bookscan All-India Bestseller List and sold over 100,000 copies.