See if your key match's any image!
There are literally thousands of different keys and the first step is to identify the type of key you have, which will help in identifying the brand of hardware it fits. This DIY guide will help the consumer to quickly identify many common key blanks. Very often the identification will quickly identify the brand of hardware.
NOTE: There are instances where the visual appearance of the key can be misleading.
Below is a chart where you can compare your key. There are many, many more keys, shapes and keyways and this illustration displays some of the more popular manufactures.
Most lock manufacturers use a distinctive bow design to identify their keys. First try to locate one that matches yours. Also look to see if your keys has a name or any numbers or letters on them. Letter/Number combinations such as SC1, KW1, Y1 etc. are important to note.
Call your local Society of Professional Locksmith member when seeking duplicates or service and make sure to provide them this information. SOPL member locksmiths are professionally trained to identify your keys.