Can someone open your garage door from the outside?

Yes, someone can open your garage door from the outside, both with authorized methods like remotes and keypads and with unauthorized methods if security is weak, so you need to understand how to secure it. Authorized methods include using a programmed remote, entering PIN on wireless keypad, using MyQ smartphone app if you have smart opener, or using an exterior emergency release key lock that disconnects trolley allowing manual lift from outside. Unauthorized methods include using a universal remote if your opener uses old fixed code rather than rolling code, as fixed codes can be captured and replayed, though modern Security+ 2.0 rolling code openers change code each time and are much harder to hack. Thieves can also use a technique called fishing, where they insert a coat hanger through top of door to hook emergency release cord inside and disconnect trolley, allowing manual lift; you can prevent this by securing emergency cord with zip tie or installing a garage shield. If you leave door unlocked with manual slide lock not engaged, someone can force door up if spring balanced. Doors with windows allow seeing inside. To prevent unauthorized opening, ensure opener uses rolling code, keep remotes secure and not in car parked outside, use MyQ alerts, engage manual slide lock when on vacation, keep gutters clean to prevent water damage that can rust lock hardware, and install deadbolt for side door. Always lock interior door to house.