The Dutch makeup guru revealed the news for the first time in a video titled "I'm Coming Out".
Nikkie continued: "I can't believe I'm saying this today to all of you for the entire world to see but damn it feels good to finally do it".
"I've always wanted to share this side of my story", she said.
"I want to start the year off with the truth". "I want to inspire little Nikkies around the world who feel insecure, who feel out of place, who feel misunderstood", she says with power and confidence that's sure to inspire everyone, transgender or otherwise. Filming this video is scary, but it feels so liberating and freeing.
She added that she was making the admission under the threat of blackmail and chose to tell her fans herself instead.
"When I was younger, I was born in the wrong body", Nikkie's voice cracks. We need to accept each other.
Added De Jager: "I am here to openly share that I am transgender". But at the end of the day, I am me.
Scarlett Johansson came under fire after she was cast to play a trans man in a decision she admitted was "tone-deaf".
She also received support from teachers, but was honest about feeling "trapped" and "angry" and was honest about the fact that some kids did not understand what she was going through.
"I'm so PROUD of you". She said she fully transitioned by the age of 19.
The makeup artist explained that she always intended on coming out to her followers eventually, but on her own terms.
Now 25, the successful beauty blogger, who has worked with beauty powerhouses like Marc Jacobs Beauty and Maybelline and featured celebrities like Drew Barrymore and Kim Kardashian West on her channel, is happily engaged to her partner Dylan. She boldly raised her middle finger towards them, quipping "I hope you sit nice on it!" She said the birth of a baby boy was a surprise to her mom and "definitely a surprise to me as soon as I had brains to think with".
YouTube has released its annual "Rewind" mashup of the year's most memorable online videos - and it's nothing like the last one.
She talked about the "evil" people who blackmailed her and threatened to leak the story.
Nikkie says she always wanted to open up about this part of her life but wanted her channel to be about her art.
That's right. Nikkie said she started taking hormones and growth stoppers, which prevented her from becoming taller, at around 14 years old; about the same time she started posting videos to YouTube.