Calculators
Opioid Equianalgesic Converter
Convert any opioid dose to its equivalent across routes and agents. Built-in cross-tolerance reduction applied before display.
equivalent dose = (input dose × ref mg) / (input ref mg) → × (1 − reduction)
Morphine IV equivalent
10.0mg
Reduction applied below: 33% (× 0.67)
Equivalent doses (after reduction)
Morphine PO
20 mg
Hydromorphone IV
1.0 mg
Hydromorphone PO
5.0 mg
Fentanyl IV
67 mcg
Display in mcg.
Oxycodone PO
13 mg
Hydrocodone PO
20 mg
Codeine PO
134 mg
Tramadol PO
67 mg
Highly variable; weak μ + SNRI.
Methadone PO
2.0 mg
Variable ratio (3:1 to 14:1 vs morphine) — consult chronic pain.
Equianalgesic doses are estimates. Patient variability, prior opioid exposure, age, and renal/hepatic function all affect actual potency. Always start lower and titrate, and consult an acute pain or palliative service for high-dose conversions (especially involving methadone or fentanyl patches).