Lever was born in a Telugu Christian family, to Prakash Rao Janumala, an operator in Hindustan Lever Ltd (HLL) plant and Karunamma Janumala in Prakasam, Andhra Pradesh, India. He was brought up in Mumbai's King's Circle area (Dharavi). His mother tongue is Telugu. He is the eldest in the family consisting of three sisters and two brothers (including his younger brother Jimmy Moses).
Lever studied in Andhra education society English high school till the seventh grade but couldn't study further because of financial problems in his family. He decided to leave school and started working odd jobs, such as selling pens on the streets of Mumbai by imitating Bollywood stars and dancing to the songs of Bollywood stars. He also spent his early years in Yakutpura, an old city of Hyderabad where he learnt the unique style of comedy acting.
During a Hindustan Lever Ltd company function, he mimicked a few senior officers, and from that day on, the workers said he was not John Rao but was Johnny Lever. When he later joined the industry, he decided to keep the name.
He started to perform stand-up comedy in musical shows (orchestras), Tabassum Hit Parade and after earning fame, joined the group of Kalyanji-Anandji, a legendary music direction duo. Even before joining Hindustan Lever, he was giving stage performances. Because of his growing absenteeisms and since he was earning well from stage shows, he quit HLL in the year 1981. He did a lot of shows and world tours with them, one of his first big tours being with Amitabh Bachchan in 1982. At one of his shows, actor Sunil Dutt noticed his talent and potential and offered him his first movie Dard Ka Rishta.
During this period, he also did a few commercials for Kachua chhap incense, directed by Shekhar Kapur. In 1986, he performed in a charity show called "Hope 86", in front of members of the Hindi film industry as a filler and was loved by the audience. His talent was recognised, which resulted in producer Gul Anand offering him the film Jalwa alongside Naseeruddin Shah.
Lever got his first break in Tum Par Hum Qurban in which the famous TV and stage compère and yesteryears actress Baby Tabassum launched her son Hoshang Govil as the leading man, and then with the film Dard Ka Rishta, thanks to Tabassum and the late Sunil Dutt. Since then, he has acted in more than 350 films including films like Tezaab, Kasam, Khatarnak and Kishen Kanhaiya . After Dard Ka Rishta, he was seen in Jalwa with Naseeruddin Shah.
His first major success came with Baazigar, and after that he was seen in movies as a supporting actor/comedian. Despite being busy with his movie roles, he continued to do live shows. One of his most memorable live performances was an impersonation of Michael Jackson at the 1999 Filmfare Awards. His most acclaimed performance was the character of "Babulal" in the film, Baazigar, directed by Abbas-Mustan. He is also remembered for some of his other famous characters, like "Chotta Chattri", "Aslam Bhai", etc. His performance in the film, Judaai and his dialogue in the movie, Abba Dabba Jabba are also notable.
He also acted in a Tulu movie, Rang. He also speaks Tulu fluently, influenced by his neighbours in Mumbai. His first Tamil feature film was Anbirkku Alavillai produced by SIMPL (Shepherd India Media Pvt. Ltd.), released in 2011. He also had a special appearance in one Telugu feature film, Criminal directed by Bollywood director Mahesh Bhatt.
Lever also appeared on Zee TV in his own show, Johny Aala Re. In 2007, he appeared as a judge on the stand-up reality show Comedy Circus.
He is the president of Cine And T.V. Artist Association (CINTAA), which has its own television show called Superstars ka Jalwa on Star Plus. He is also the president of MAAM (Mimicry Artist Association Mumbai), and has done thousands of live shows all over the world. His younger brother, Jimmy Moses, is also a comedian and mimicry artist.
He is married to Sujatha and has two children, a daughter Jamie who is a stand-up comedian too and a son Jesse.
Lever is a practicing Christian. When asked about his transition, Lever replied:
It was God’s will. I had always been a religious person, but one incident changed my life. My son was diagnosed with cancer. I was helpless and turned to God for help. I stopped working in films and spent all my time praying for him. Ten days later, when he was taken for a test, the doctors were surprised because the cancer had vanished. It was the beginning of a new life for me.
In 1998, Lever was convicted and sentenced to seven days imprisonment for disrespecting the Indian National Anthem, constitution and the flag at a private function hosted by Anees Ibrahim Kaskar, brother of global terrorist Dawood Ibrahim, head of the infamous D-Company. However, he was relieved of all charges subsequently.