CRI Calculator for Dogs
Calculate constant rate infusion (CRI) amounts and rates for analgesics, sedatives, and vasopressors in canine patients.
What Is the CRI Calculator for Dogs?
Calculate constant rate infusion (CRI) amounts and rates for analgesics, sedatives, and vasopressors in canine patients.
Calculate the exact amount of drug to add to a fluid bag for CRI administration at a given fluid rate — for fentanyl, morphine, ketamine, lidocaine, dopamine, and more.
Every result is based on published veterinary research and breed-size-specific growth data — not generic averages. This tool is completely free, works instantly in your browser, and requires no account or sign-up.
How to Use This Calculator
Fill in the required fields above — typically your dog's weight, age, or breed size. Every field has a clear label and hint.
Press the calculate button to get your instant result. No page reload, no account needed, no waiting.
Your result appears immediately below the calculator. It includes the primary answer plus additional context where relevant.
Share, print, or save your result. Always discuss health-related results with your veterinarian before making decisions.
How It Works
CRI calculations follow the formula: Drug to add (mg) = Patient weight (kg) x Target dose x Bag volume (ml) / Fluid rate (ml/hr). For drugs dosed per minute, an additional factor of 60 converts the rate. The bag is then run at the specified fluid rate to deliver the target dose continuously. Always verify with a second clinician before administration.
Veterinary Research
Every formula is derived from peer-reviewed veterinary studies and clinical guidelines, not guesswork or generic rules.
Instant Results
No page reload, no waiting, no account needed. Enter your details and your result appears immediately.
100% Private
All calculations happen in your browser. Nothing you enter is ever stored on our servers or shared with anyone.
Always Free
Every calculator on Doggy Calculators is and will always be completely free to use — no premium tier, no catch.
Frequently Asked Questions
Sources & References
This calculator's formulas are based on the following peer-reviewed and authoritative veterinary sources:
- Merck Veterinary Manual u2014 Clinical Reference — Clinical formulas, normal reference ranges, and diagnostic criteria
- WSAVA Guidelines for Veterinary Practice — International veterinary clinical standards
- Ettinger's Textbook of Veterinary Internal Medicine — Advanced clinical reference for fluid therapy, haematology, and diagnostics
- RECOVER Initiative u2014 CPR Guidelines — Emergency drug dosing and resuscitation protocols
⚠️ These calculators are reference tools only. Always consult a licensed veterinarian before administering medication or making medical decisions.