In the 2010 Marvel movie Iron Man 2, Black Widow made her debut in the Marvel Cinematic Universe as an agent of S.H.I.E.L.D.

Coupled with the Easter egg at the end of Captain Marvel, Black Widow appeared in a total of 8 Marvel movies.
Appearing so many times, Black Widow went from a supporting role to a well-known protagonist. Following the Reunion Of The Big Three, Black Widow is about to have her own independent film.
From 2010 to 2020, a full 10 years, it was not easy for the role of Black Widow and the actor "Scarlett Johansson".
"Scarlett Johansson" was born in 1984 and is 35 years old this year.
So, without thinking about the question, how old is Black Widow in the Black Widow independent film?
First, we have to confirm the year of birth of black widow.
In the Marvel Cinematic Universe, Black Widow's birth year is 1984 (exactly the same as the actor), and this information can be confirmed from two sources.
One is in the Marvel movie "Captain America 2"
Zola's artificial intelligence at S.H.I.E.L.D.'s secret base briefly introduced Black Widow, mentioning that Black Widow was born in 1984.
The second is in the official comic strip of the prelude to the Black Widow movie
General Ross shares some of her information in pursuit of Black Widow.
It is also explicitly mentioned that "Black Widow was born in Russia in 1984".
Early in the promotion of the Black Widow film, director "Kate Sautlán" revealed the timeline of the film.
Black Widow's main story follows Captain America: Civil War and before Avengers: Infinity War.
Similarly, this timeline is also confirmed in the official comic of the Black Widow movie prelude.
During the recent Civil War, General Ross suspected that Black Widow had helped Captain America escape.
General Ross once asked The Panther, but the Panther refused to answer the question.
Therefore, General Ross had to hunt down Black Widow himself.
According to the Timeline of Marvel Movies, Captain America: Civil War is 2016, Avengers 3: Infinity War is 2018, and Avengers 4 is 2023.
Black Widow is 31 years old during the Civil War and 33 years old during Infinity War.
That is to say, in the "Black Widow" independent film, the actual age of Black Widow is about 32 years old.
Of course, "Black Widow" involves the history of the Red House in the 90s, the film contains a lot of flashback shots, and the teenager version of Black Widow will also meet with everyone.
On the imdb website,"Black Widow" cast list, it is shown that "Al Anderson" will play the teenage version of Black Widow (she once starred in "Resident Evil: Final Chapter" and is now 12 years old).
The above is about Black Widow's age sharing in independent movies, I hope to refer to you.