Adderall to Vyvanse Conversion Calculator
Use this educational calculator to estimate a rough Vyvanse equivalent from a current Adderall regimen. Because Adderall and Vyvanse are not milligram-for-milligram substitutes, this tool should be used only as a discussion aid with a licensed prescriber or pharmacist.
Dose Conversion Estimator
Enter the amount taken each time, not the full day total.
For XR, this is commonly 1. Use your actual prescribed daily frequency.
The estimate is based on total daily mixed amphetamine salts exposure.
Vyvanse marketed strengths are 10, 20, 30, 40, 50, 60, and 70 mg.
Enter your current Adderall schedule and click Calculate Estimate.
Dose Snapshot
The chart compares your current total daily Adderall dose with the approximate Vyvanse estimate and the FDA-labeled Vyvanse maximum daily dose of 70 mg.
How to use an Adderall to Vyvanse conversion calculator safely
An adderall to vyvanse conversion calculator is best understood as a planning tool, not a prescribing tool. Both medications are stimulants used in attention-deficit/hyperactivity disorder management, but they are formulated differently, absorbed differently, and labeled differently. Adderall contains mixed amphetamine salts, while Vyvanse contains lisdexamfetamine, a prodrug that must be converted in the body to active dextroamphetamine. Because of that difference, a direct 1-to-1 milligram swap is not appropriate.
Many clinicians use a rough rule of thumb that the estimated Vyvanse dose is about 2.6 times the total daily Adderall dose. That estimate is what this calculator applies. For example, a person taking Adderall 10 mg twice daily has a total daily dose of 20 mg. Multiplying 20 mg by 2.6 gives an estimated Vyvanse equivalent of 52 mg, which is often rounded to the nearest marketed strength, such as 50 mg. That does not mean 50 mg will be the correct prescribed dose for every patient. It only means the numbers are in a similar range for a medication review conversation.
Why the conversion is only approximate
Even when the arithmetic looks straightforward, stimulant conversion is not purely mathematical. Adderall contains multiple amphetamine salts, and the immediate-release and extended-release versions can feel different across the day. Vyvanse has a slower activation profile because it is a prodrug, and many patients report a smoother onset or a longer tail of symptom coverage. Some people need a lower starting Vyvanse dose than a calculator suggests because they are sensitive to stimulants, prone to insomnia, or have appetite suppression. Others may need careful titration upward if symptom control is incomplete.
That is why a good calculator should do two things at once: provide a realistic estimate and clearly warn users not to self-convert without supervision. The safest process is to calculate a ballpark number, compare that estimate with available Vyvanse strengths, and then let the clinician choose a starting dose and titration schedule based on symptoms, age, side effects, cardiovascular history, and concurrent medications.
Basic conversion method used by this calculator
- Enter the Adderall dose taken each time.
- Select how many times per day it is taken.
- Calculate the total daily Adderall dose.
- Multiply the total daily dose by 2.6.
- Optionally round the result to the nearest marketed Vyvanse strength.
This calculator therefore uses the following formula:
Total daily Adderall dose = dose per administration × doses per day
Estimated Vyvanse dose = total daily Adderall dose × 2.6
Example conversions
- Adderall 5 mg twice daily = 10 mg/day total → estimated Vyvanse 26 mg → nearest marketed strength 30 mg
- Adderall 10 mg twice daily = 20 mg/day total → estimated Vyvanse 52 mg → nearest marketed strength 50 mg
- Adderall 15 mg twice daily = 30 mg/day total → estimated Vyvanse 78 mg → above the FDA-labeled 70 mg/day maximum
- Adderall XR 20 mg once daily = 20 mg/day total → estimated Vyvanse 52 mg → nearest marketed strength 50 mg
| Medication | Common labeled strengths | Usual daily pattern | Important note |
|---|---|---|---|
| Adderall IR | 5, 7.5, 10, 12.5, 15, 20, 30 mg tablets | Often split into 1-3 doses daily | Shorter acting pattern may require multiple daily doses. |
| Adderall XR | 5, 10, 15, 20, 25, 30 mg capsules | Typically once daily | Extended-release profile is not identical to Vyvanse despite similar treatment goals. |
| Vyvanse | 10, 20, 30, 40, 50, 60, 70 mg capsules and chewables | Once daily | FDA-labeled maximum daily dose is 70 mg. |
Important clinical issues that a calculator cannot fully capture
A conversion calculator helps with dose math, but it cannot replace clinical judgment. Prescribers often take a broader view that includes the medication’s duration of action, the patient’s work or school day, coexisting anxiety, blood pressure trends, appetite and weight concerns, headache patterns, and sleep quality. If a person has done well on Adderall but experiences rebound irritability when it wears off, the clinician may prefer a different Vyvanse starting point than the calculator’s rounded estimate. If a person had side effects on Adderall, the clinician may intentionally start lower than the rough equivalent.
Another key issue is that insurance coverage and formularies can influence real-world prescribing. During shortages or plan changes, patients may look for a direct numerical switch. That is understandable, but it can be risky if it skips medical review. The better approach is to use the estimated conversion as a structured question for the visit: “I’m taking this much Adderall now; if we switched to Vyvanse, what would be a cautious starting dose and why?”
Situations that deserve extra caution
- History of high blood pressure, structural heart disease, palpitations, chest pain, or syncope
- Marked anxiety, panic symptoms, agitation, or stimulant sensitivity
- Insomnia or delayed sleep onset that is already difficult to manage
- Appetite suppression, weight loss, or eating disorder history
- Use of other activating medications or substances
- Pregnancy, breastfeeding, or medication use in younger children without specialist review
Why formulation matters even if the total daily milligrams are the same
Suppose two people are each taking 20 mg of Adderall per day. One takes Adderall IR 10 mg twice daily. The other takes Adderall XR 20 mg once daily. Their total milligrams match, but the day-to-day feel may not. The person using the immediate-release form may experience a more distinct rise and fall after each dose. The person using extended-release may feel a broader coverage window. Vyvanse, because of its prodrug design, often has a smoother onset and can feel less abrupt to some patients. As a result, a clinician may make a different practical recommendation even when a conversion calculator gives the same numerical estimate.
| Total daily Adderall dose | 2.6x estimate | Nearest marketed Vyvanse strength | Practical comment |
|---|---|---|---|
| 10 mg/day | 26 mg | 30 mg | Often close to a common entry point, but sensitivity still matters. |
| 15 mg/day | 39 mg | 40 mg | A common midrange estimate when stepping up from lower Adderall exposure. |
| 20 mg/day | 52 mg | 50 mg | One of the most frequently discussed conversion examples. |
| 25 mg/day | 65 mg | 70 mg | Already near the labeled upper boundary for Vyvanse. |
| 30 mg/day | 78 mg | Not directly available within labeled max | Requires prescriber review because the estimate exceeds 70 mg/day. |
What “correct” means in stimulant conversion
When patients search for an adderall to vyvanse conversion calculator, they often want a single correct answer. In practice, there are two kinds of correctness. The first is mathematical correctness, which means using a recognized approximate factor such as 2.6 and rounding logically to available strengths. The second is clinical correctness, which means selecting a dose that is safe, tolerable, and effective for the individual. A good conversion tool can provide the first kind of correctness. Only a licensed clinician can provide the second.
This distinction matters because stimulants are not simply interchangeable by weight. Prescribers may also choose to under-convert at first in order to watch for insomnia, appetite changes, elevated heart rate, or blood pressure effects. They may reassess after several days or a week and adjust the plan. Some patients ultimately land above or below the calculator’s rounded estimate because real response is individualized.
How to discuss the result with your clinician
- Bring your exact current regimen, including dose, formulation, and timing.
- Show the estimated Vyvanse equivalent and ask whether it makes clinical sense.
- Discuss what problem the switch is intended to solve: duration, side effects, convenience, supply, or cost.
- Ask whether the prescriber wants to start lower than the estimate and titrate upward.
- Review blood pressure, pulse, sleep, appetite, and any history of anxiety or cardiovascular concerns.
Frequently asked questions
Is Adderall 20 mg the same as Vyvanse 20 mg? No. They are not milligram-for-milligram equivalents. A rough rule commonly cited in clinical discussions is that Vyvanse may be around 2.6 times the total daily Adderall dose.
Can I switch from Adderall IR to Vyvanse overnight on my own? No. Even if the math seems simple, self-adjusting stimulant therapy can increase side effect risk or leave symptoms uncontrolled.
Why does the calculator round the result? Vyvanse is sold in fixed marketed strengths, so the exact estimate often has to be rounded to a practical capsule strength. Rounding still requires a clinician review.
What if the estimate is above 70 mg? The FDA-labeled maximum daily dose for Vyvanse is 70 mg, so any estimate above that should be treated as a sign that a direct conversion needs prescriber judgment and not a do-it-yourself substitution.
Authoritative references for further reading
If you want official drug information rather than forum advice, review these authoritative resources and discuss them with your healthcare professional:
- MedlinePlus: Dextroamphetamine and Amphetamine
- NIH MedlinePlus: Amphetamine combination products safety information
- DailyMed: Lisdexamfetamine prescribing information
- U.S. Food and Drug Administration
Bottom line
An adderall to vyvanse conversion calculator is most useful when it turns a confusing medication switch into a clear, structured conversation. The common estimate of Vyvanse being roughly 2.6 times the total daily Adderall dose can be helpful, but it is still only an estimate. The right final dose depends on symptom control, side effects, the reason for the switch, and the prescriber’s clinical judgment. Use the calculator to prepare for your visit, not to replace it.