Which specific platform (Steam, mobile, or legacy Flash) are you playing on so I can give you more targeted instructions? Where I can find the Bloons TD 5 Deluxe save file? - Arqade

If playing the older Flash version, the save is often a .sol file found in %APPDATA%\Macromedia\Flash Player\#SharedObjects . These can be edited using a minerva .SOL editor . 2. Manual Text/XML Editing

Excited, xXxBloonMasterxXx downloaded the updated save editor and launched it. He carefully selected his BTD5 save file and began to edit. With a few quick clicks, he boosted his Super Monkey's level to 20 and maxed out its damage output.

If you are looking to find your actual player progress save file to back it up or move it to a new computer, look in the following directory: Steam (Windows):