Dog nails should generally be trimmed about once a month on average, but this can vary based on factors such as breed, size, age, activity level, and the surfaces your dog normally walks on.

Recommended Frequencies by Size:

• Small breeds: every 3-4 weeks
• Medium breeds: every 4-5 weeks
• Large breeds: every 6-7 weeks

Activity Level Considerations:

• Active dogs that regularly walk on hard surfaces may naturally wear down their nails and need less frequent trimming.
• Sedentary dogs usually require more frequent trimming as their nails are less worn.

Practical Tips:

• Check your dog's nails every couple of weeks to monitor growth.
• Trim nails gradually to avoid cutting into the quick, which is painful and bleeds.
• Trim at a 45-degree angle small bits at a time.
• If your dog is anxious, do short sessions with positive reinforcement.

Adjust your trimming schedule to your dog's unique needs to keep their nails at a healthy and comfortable length. Regular observation is key to knowing when a trim is necessary to avoid overgrowth and related problems.