Choose the exact input
before calculating.
Use this selection page to copy the exact analyte, specimen, method and cutoff from a laboratory order or report. No substance is prefilled, and the calculator never predicts a guaranteed negative date.
Choose an exact substance or analyte profile
Use this selection page to copy the exact analyte, specimen, method and cutoff from a laboratory order or report. No substance is prefilled, and the calculator never predicts a guaranteed negative date.
- Start with the laboratory order or report: exact analyte, specimen, method and cutoff are required.
- Profile type: not-selected; a broad internet detection range is not substituted for a laboratory order or report.
A drug test is a specimen-specific measurement against a defined method and cutoff. SAMHSA guidance does not support converting a broad internet detection range into a guaranteed negative date.
Context matters.
- Do not use this page to time drug use, defeat a test or decide that driving, work, medication use or another safety-sensitive activity is safe.
- An initial non-negative screen may require confirmatory testing and review. A reported negative means the analyte was not reported at or above that test's cutoff; it is not proof of no exposure or no impairment.
- For a clinical result, discuss the exact laboratory report with the treating clinician. For a regulated workplace result, use the program's Medical Review Officer and challenge / retest process.
Sources & scope
The calculation guide and this source trail show what the result means, where the rule came from and when it was last reviewed. This is source-and-calculation QA, not a claim of medical, legal, tax or other professional review; time-sensitive decisions still belong with the linked authority.