🐾 Understanding Dog Bite Levels in 2025: A Vet’s Guide to Severity, Safety, and Action 🐶🛑

By Dr Duncan Houston BVSc, Ask A Vet Blog
Published: July 7, 2025

Bite incidents between dogs and humans—or even between familiar dogs—can be complex and dangerous. Understanding the level of a bite is essential for assessing risk, determining behavioral strategies, and ensuring safety for everyone involved. Here's a detailed breakdown of the six bite levels, first described by Dr. Ian Dunbar and modified by Dr. Sophia Yin 🩺🐾

🔍 Level 1 – Pre-Bite (Air Snap)

⚠️ The dog snaps at the air but makes no contact with the skin. This is a warning—often misunderstood as a failed bite. In reality, dogs have precise control. This level means:

• The dog wants space
• There were likely missed early signals of fear or stress 😰

👉 Action: Avoid punishment. Learn canine body language and consult a behavior professional early 🧠

🦷 Level 2 – Near-Bite or Inhibited Contact

The dog makes tooth contact with skin, but there’s no puncture. This includes soft “warning” bites or lunging with contact but no damage. It’s still serious:

• 🧠 It shows increasing stress and arousal
• ⚠️ Without help, it can escalate

🩸 Level 3A – Single Bite with Shallow Puncture

This is a reportable bite. The skin is punctured but not deeper than half the length of the dog’s canine tooth. It’s painful and signals danger:

• The dog has now used their teeth to communicate fear or overwhelm
• 📄 Medical care and documentation are often required

🩹 Level 3B – Multiple Bites with Shallow Punctures

This means escalated arousal. The dog may not be thinking clearly and is reacting repeatedly. Multiple shallow bites suggest:

• The dog was unable to stop after the first bite
• 🌪️ Emotions or fear are overwhelming them

⚠️ Behavior modification and safety protocols are urgently needed.

💥 Level 4 – Single Deep Bite or Bite with Head Shake

This is a serious, dangerous bite. It punctures deeper than the length of the canine or includes tearing of tissue due to a head shake. It signals:

• Complete loss of bite inhibition 😬
• High risk to children or vulnerable individuals

👩‍⚕️ These dogs pose a liability. Rehoming, secure management, and long-term treatment plans must be considered.

🩸🩸 Level 5 – Multiple Deep Bites

This dog has bitten multiple times at level 4 severity. Often seen in dogs with extensive bite history or in severe fear/aggression cases. The dog is:

• Actively harming, not just warning
• ⚠️ Highly dangerous and likely cannot live safely without significant restrictions

☠️ Level 6 – Death or Flesh Consumption

This tragic level involves lethal or near-lethal force, including dogs that:

• 🧸 Kill infants or small animals
• 🥩 Bite with tissue loss or cannibalism

This is the rarest but most catastrophic level. Dogs biting this severely may do so out of extreme fear, overaroused play, or redirected aggression.

🛠️ What To Do If Your Dog Bites

Any bite—regardless of level—should be seen as a communication attempt. Dogs bite when their signals are missed or ignored. Your action plan should include:

• 🏥 Immediate vet care if the bite was uncharacteristic
• 🐕‍⚕️ Behavior consult with a certified professional
• 🧠 Avoidance of punishment
• 📚 Educate your household about body language
• 📋 Management (muzzles, barriers, safe spaces)

🧠 Early Intervention is Key

Level 1 and 2 bites are clear opportunities for intervention before behavior escalates. Catch it early, act compassionately, and use professional support such as AskAVet.com to speak with a vet or behavior expert.

📲 For Immediate Help

Speak with a licensed vet on the Ask A Vet app if your dog shows signs of fear or escalating behavior. The sooner you act, the better the outcome for your dog and your family 💛🐶