The choice between 6-inch or 7-inch gutters depends on several factors, including the climate in your area, the size and pitch of your roof, and the average rainfall intensity.

6-Inch Gutters:

These are the standard size for most residential properties. They work well in areas with moderate rainfall and standard-sized roofs. If you live in a region with infrequent heavy rain, 6-inch gutters should suffice.
7-Inch Gutters:

These are typically recommended for homes with larger roofs or in regions that experience heavy rainfall or occasional downpours. The larger capacity of 7-inch gutters allows them to handle more water, reducing the risk of overflow and water damage during heavy rain events.
To determine the ideal size for your gutters, it’s advisable to consult with a professional gutter installation specialist. They can assess your specific needs based on your location and property characteristics to ensure your gutter system effectively manages rainwater and protects your home from potential water damage.