Are there any plagiarism checkers that actually work?

VS code was really promising for a bit, but you can only check 10 times a day for free. I have to write my 50 page paper in the next 4 days, and I also have to write an 8 page paper over the same period. <br><br>I spend a few hours on each, and I need to check for plagiarism because I stay up for 15 hours in bed writing, and it gets really easy to forget what you wrote and what you literally copied and pasted from google.