π Opioid MME Calculator
Convert any opioid dose to morphine milligram equivalents per day.
For informational purposes only, not medical advice. Consult a healthcare professional.
Morphine milligram equivalents, or MME, put every opioid on one scale. A 10 mg oxycodone tablet is not equal to a 10 mg morphine tablet, because oxycodone is stronger per milligram. MME converts any opioid dose into the equivalent milligrams of morphine per day, which is the number the CDC uses in its prescribing guideline to flag risky doses. This calculator applies the CDC conversion factors to your prescription and shows the daily MME total with the CDC caution thresholds.
How to Use This Calculator
Pick the opioid from the list, enter the strength of each tablet, capsule, or patch, and how many doses are taken in a day. The calculator multiplies dose by the CDC conversion factor and by daily frequency.
Select the opioid. The conversion factor next to each name comes from the CDC clinical practice guideline table, so fentanyl patch uses mcg per hour while everything else uses mg.
Enter the dose per unit and doses per day exactly as written on the prescription label. If two opioids are taken, calculate each one separately and add the results.
Read the total MME per day plus the CDC risk band. At 50 or more MME per day the CDC advises extra caution, and at 90 or more it advises avoiding the dose or tapering.
How the Math Works
The math is simple multiplication. Daily MME equals the dose per unit times the number of doses per day times the drug-specific conversion factor. The factors come from the CDC 2022 clinical practice guideline for prescribing opioids: morphine 1, hydrocodone 1, oxycodone 1.5, hydromorphone 4, oxymorphone 3, codeine 0.15, tramadol 0.1, tapentadol 0.4, and transdermal fentanyl 2.4 per mcg per hour. The CDC bands are 50 MME per day, where clinicians should carefully reassess the balance of benefit and risk, and 90 MME per day, where the guideline advises avoiding escalation and considering a taper. These cutoffs describe population risk, not a personal safe limit.
Worked Example
A patient takes oxycodone 10 mg tablets four times a day. The factor for oxycodone is 1.5, so each 10 mg tablet equals 15 MME, and four tablets give 60.0 MME/day for the day, which lands in the Caution: 50+ MME/day band the calculator reports. That crosses the CDC 50 MME caution line, which is exactly the point where the guideline says the prescriber should pause and reassess whether the benefit still outweighs the risk.
Reading Your Result
The result is a risk signal, not a verdict on your prescription. Below 50 MME per day, overdose risk in population studies is comparatively low, though never zero. From 50 to 89, risk roughly doubles compared with lower doses and the CDC advises documented reassessment. At 90 and above, risk climbs steeply and the guideline advises against starting there and recommends tapering plans for patients already there. Never cut a dose on your own because of a calculator number. Sudden drops cause withdrawal and can push people toward riskier sources, so any change belongs in a conversation with the prescriber.
| Daily MME | CDC band | What it means |
|---|---|---|
| Under 20 | Lower range | Typical starting range for acute pain |
| 20 to 49 | Moderate | Reassess benefit vs risk at follow-ups |
| 50 to 89 | Caution | CDC advises careful reassessment |
| 90 or more | High risk | Avoid escalation, consider taper plan |
Limitations
Conversion factors are population averages and do not capture individual tolerance, metabolism, drug interactions, or sleep apnea, all of which shift real risk. Methadone is deliberately left out because its factor changes with dose and it is unsafe to convert with a simple multiplier. This tool cannot tell you whether a prescription is appropriate, and it must never be used to adjust a dose without the prescriber.
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For informational purposes only, not medical advice. Consult a healthcare professional.
Frequently Asked Questions
What is MME in plain English?
MME stands for morphine milligram equivalents. It answers one question: how strong is this opioid dose compared with plain morphine? A 10 mg oxycodone tablet counts as 15 MME because oxycodone is about 1.5 times as potent per milligram. Adding every opioid you take into one MME total is how clinicians compare regimens and how the CDC sets its risk thresholds.
Where do the conversion factors come from?
From the CDC clinical practice guideline for prescribing opioids for pain, published in 2022. The table lists each common opioid with its multiplier relative to morphine. This calculator uses those exact factors, including 2.4 per mcg per hour for fentanyl patches, which is the one people most often get wrong.
Why is 50 MME per day a cutoff?
In large population studies, overdose risk starts rising noticeably around 50 MME per day. The CDC chose it as the line where prescribers should carefully reassess whether the pain relief justifies the risk. It is a population statistic, not a guarantee about any one person, but crossing it is a legitimate reason to ask your prescriber for a review.
What does the 90 MME threshold mean?
At 90 MME per day and above, overdose risk is several times higher than at low doses. The CDC advises clinicians to avoid escalating to this range and to discuss tapering with patients already there. Again, this is guidance for a clinical conversation, not an instruction to cut a dose yourself.
How do I add two different opioids together?
Calculate each one separately with its own factor and dose, then add the two MME totals. The calculator has a field for the number of opioids only as a reminder; the correct method is one calculation per drug, then a sum. If you take a long-acting plus a breakthrough opioid, both count toward the daily total.
Does the fentanyl patch really use a different unit?
Yes. For transdermal fentanyl the factor 2.4 multiplies the patch strength in micrograms per hour, not milligrams. A 25 mcg per hour patch equals 60 MME per day. Mixing up the units is one of the most dangerous conversion errors, which is why the calculator labels the field explicitly.
Why is methadone not in the list?
Methadone breaks the simple-multiplier model. Its conversion factor rises with the dose, from about 3 at low doses to 12 or more at high doses, and it has a long, unpredictable half-life. Any methadone conversion needs a clinician and a proper table, so leaving it out of a one-line calculator is the safe choice.
Can I use this to taper my own dose?
No. Tapering opioids without medical supervision causes withdrawal and sharply raises the risk of turning to illicit sources. The MME number is useful information to bring to your prescriber, who can build a taper plan with you. Use the result as a conversation starter, never as a dosing instruction.
Does MME account for tolerance?
Not at all. Two people on 60 MME per day can have completely different risk profiles depending on tolerance, age, lung disease, sleep apnea, alcohol use, and interacting sedatives like benzodiazepines. The number standardizes the dose, not the person. That is why the bands are screening signals rather than personal verdicts.
Is a low MME dose automatically safe?
No dose of opioids is risk-free. Dependence can develop even at low doses taken for more than a few days, and combining any opioid with alcohol or sleep medications raises overdose risk at any MME level. The thresholds mark where population risk climbs, not a line below which nothing bad happens.