• Federal
  • DOT · Federal
  • Urine
  • Oral fluid

What Is a Drug-Test Cutoff?

Short answer

A cutoff is the concentration at or above which a laboratory reports a result as positive. Below it, the result is reported negative — even if a trace was detected. Every analyte has two: a higher screening cutoff and a lower confirmatory one, and both must be met. Cutoffs are reporting thresholds set in advance, not measures of how much you used or whether you were impaired.

Last verified 17 Aug 2026 Reviewed with Dr. Matthew Nuesse, DOT Certified Medical Examiner

What matters most

  • A cutoff is a reporting threshold, not a measurement of use or impairment.
  • Each analyte has a screening cutoff and a lower confirmatory cutoff; both must be met.
  • Below the cutoff is reported negative even when a trace amount is detected.
  • The same drug has different cutoffs in different programmes and different specimens.
  • At-home tests set their own levels, which is why they can disagree with a laboratory.

What a cutoff is

A cutoff concentration is a line drawn before your sample ever existed. At or above it, the laboratory reports positive; below it, negative Source 1DOT ODAPC49 CFR §40.85 — What are the drug test cutoff concentrations? — checked 17 Aug 2026Source 2eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026. It is an administrative threshold, chosen to balance detection against the risk of reporting trace amounts, and it is fixed in advance for everyone tested under that programme.

This is why the phrase just barely over does not describe a different kind of result. The line is the line, and a laboratory reports which side of it your sample fell on.

Why every analyte has two

The screening cutoff is set higher because the screening method is broad — it reacts to a family of similar compounds, so a higher threshold keeps the volume of follow-up work manageable. The confirmatory cutoff can sit lower because the confirmatory method identifies the exact compound and there is no longer any risk of mistaking a lookalike for the target Source 1DOT ODAPC49 CFR §40.85 — What are the drug test cutoff concentrations? — checked 17 Aug 2026Source 2eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026Source 5eCFR49 CFR Part 40 — Procedures for Transportation Workplace Drug and Alcohol Testing Programs — checked 17 Aug 2026.

Both have to be crossed, in order, on the same sample. A screen above its cutoff and a confirmation below the confirmatory cutoff is reported negative.

Federal cutoffs are not the only cutoffs

Federal (DOT): DOT testing uses the table in 49 CFR §40.85, which has not changed since May 2023 Source 1DOT ODAPC49 CFR §40.85 — What are the drug test cutoff concentrations? — checked 17 Aug 2026Source 2eCFR49 CFR §40.85 (current text) — checked 17 Aug 2026.

Federal (HHS): Federal civilian employees are tested under a separate set of panels published by the Department of Health and Human Services, which overlap heavily with the DOT numbers but are not identical, and which also cover oral fluid Source 3HHSMandatory Guidelines for Federal Workplace Drug Testing Programs — Authorized Testing Panels — checked 17 Aug 2026.

The table below makes the point better than prose does: marijuana in urine screens at 50 ng/mL, and the same drug in oral fluid screens in single figures. The numbers are not comparable across specimen types, because the concentrations found in each are different. A number quoted without its programme and its specimen is close to meaningless.

Cutoffs and at-home tests

An at-home test has a cutoff too, chosen by whoever made it, and it may be higher or lower than the laboratory threshold that would apply to you. That is the mechanical reason a home test and a laboratory can disagree without either being defective — they are answering the same question against different lines Source 4FDADrugs of Abuse Home Use Test — checked 17 Aug 2026.

If you are using a home test to anticipate a laboratory result, the level printed on the packaging is the number that matters, and it is worth checking it against the programme you will actually be tested under.

What a cutoff cannot tell you

A cutoff cannot tell you when a substance entered your system, how much was taken, or whether you were impaired at any point. Those are different questions, and a threshold comparison on a urine sample does not answer any of them. A result tells you which side of a pre-set line one sample fell on, on one day.

The same drug, different thresholds: marijuana cutoffs by programme and specimen (ng/mL, verified 17 August 2026)

The same drug, different thresholds: marijuana cutoffs by programme and specimen (ng/mL, verified 17 August 2026)
Programme and specimenInitial cutoffConfirmatory cutoff
DOT urine (49 CFR §40.85)5015
HHS federal-agency urine5015
HHS federal-agency oral fluid2–42

What this means for you

When you read a number anywhere — on a packet, in a forum, in an article — ask two things: which programme, and which specimen. Without both, the number cannot be compared to anything. And if you are trying to reason backwards from a cutoff to what you did or when, the arithmetic does not work: detection depends on the individual, and a threshold is not a dose.

50 ng/mL is the number most of this page turns on. A home strip calibrated to it reads the same threshold a laboratory immunoassay screens at — it just cannot tell you the concentration behind the line.

Rules differ by state and employer. This section describes federal requirements. Your state law or your employer’s written policy may add rules on top of them.

When the answer changes

Alcohol works differently. It is reported as a concentration measured against action levels rather than as a positive or negative against a detection cutoff, and unlike other analytes those numbers do relate to recent consumption. Fentanyl is another wrinkle: it appears on the HHS federal-agency panel with its own cutoffs, but it is not on the DOT panel at all, so there is no DOT cutoff for it to be over or under.

Dr. Matthew Nuesse
Medical review

Dr. Matthew Nuesse

DOT Certified Medical Examiner

Dr. Matthew Nuesse is a DOT Certified Medical Examiner who reviews Exploro's drug testing guides for medical and procedural accuracy.

Common questions

It is the concentration at or above which a laboratory reports a result as positive. Below it, the result is reported negative — even if a trace amount was detected. Cutoffs are a reporting threshold, not a measure of impairment.

Source:DOT §40.85, 49 CFR §40.85 (eCFR)

The laboratory. A home test is a screening device set to its own cutoff, and the FDA describes consumer tests as qualitative — they suggest whether a substance may be present, not how much. Laboratory testing is the reliable way to confirm a result.

Source:FDA — Home use tests, FDA — Drugs of abuse tests

No. The DOT panel covers marijuana, cocaine, amphetamines, PCP and a set of opioids that does not include fentanyl. A rule to add fentanyl was proposed in September 2025 but has not taken effect, so it is not tested for on a DOT test today.

Source:DOT NPRM — fentanyl (proposed), DOT §40.85

Official sources

Every factual claim above is drawn from these sources. Each was opened and checked on the date shown. Where a rule differs between agencies, the source that governs is named in the text.

  1. DOT ODAPC · DOT §40.85

    49 CFR §40.85 — What are the drug test cutoff concentrations?

    Checked 17 Aug 2026
    View official source ↗ (opens in a new tab)
  2. eCFR · 49 CFR §40.85 (eCFR)

    49 CFR §40.85 (current text)

    Checked 17 Aug 2026
    View official source ↗ (opens in a new tab)
  3. HHS · HHS Mandatory Guidelines (2026)

    Mandatory Guidelines for Federal Workplace Drug Testing Programs — Authorized Testing Panels

    Effective 07 Jul 2025 · Published 13 Mar 2026 · Checked 17 Aug 2026
    View official source ↗ (opens in a new tab)
  4. FDA · FDA — Home use tests

    Drugs of Abuse Home Use Test

    Checked 17 Aug 2026
    View official source ↗ (opens in a new tab)
  5. eCFR · 49 CFR Part 40 (eCFR)

    49 CFR Part 40 — Procedures for Transportation Workplace Drug and Alcohol Testing Programs

    Checked 17 Aug 2026
    View official source ↗ (opens in a new tab)

From Exploro

Test at home

A home test is a screening step. It tells you whether a substance is above or below that test’s cutoff — not how much, and not what a laboratory would report.

Exploro makes these tests. Star ratings are from Amazon customer reviews and are refreshed periodically; current prices and full instructions are on each product page.