West Yorkshire Police traced the illegal activity to an IP address on Templegate Avenue in Halton and raided the property on June 22 last year.
They arrested Thomas William Messruther-Brown and seized his phone and laptop.
Most of the illegal material was found on his laptop, with two videos found on the 22-year-old’s phone.
In total, there were 143 videos and 22 images in category A – the most serious – 299 videos and 38 images in category B and 17 videos and 25 images in category C.
Police determined he uploaded the vile videos and photos from February 2014 to May 2021, and searched for them on illegal websites and cloud storage devices.
The abused children ranged in age from 6 to 16, and some of the videos were over an hour long, prosecutor Philip Adams said. Leeds Crown Court this week.
In his first interview with police he denied any wrongdoing, but in a second interview five months later he gave a prepared statement in which he accepted responsibility.
He admitted three counts of possessing unlawful images.
Mitigating, Sean Smith said Messruther-Brown had no prior convictions but had already completed the safer lives that helps online sex offenders understand their behavior.
He said: “It is clear that this is a person who has asked for and received significant help.
“He spent long periods of solitary confinement in his bedroom and explored his sexuality at a young age, all of which contributed to the occurrence of these offences.”
Judge Neil Clark referenced Messruther-Brown’s isolation and being diagnosed with autism.
He told her: “You have never troubled the courts before and I think it is unlikely that you will in the future.
“It’s important that you asked for help to make sure you never do it again. You’ve already taken important steps.”
He gave her an 18-month community order with 30 days of rehabilitation, ordered her to sign the sex offender registry for five years, and gave her a five-year Sexual Harm Prevention Order (SHPO), which will limit her Internet use.