ALT levels: what's normal, high and low
An enzyme found mainly in the liver. Elevations can signal liver cell injury.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
ALT is measured with a standard blood draw after an 8–12 hour fast. A typical reference range is 7.00 – 55.0 U/L (male, age 18+; more bands below). At TestWell it's $22.99 all-in as Comprehensive Metabolic Panel, results in 1–3 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
- Units
- U/L / IU/L
- Sample
- Blood draw
- Fasting
- 8–12 hours
- Results
- 1–3 business days
- Price
- $22.99
- Labs
- Quest or Labcorp · BioReference in NY/NJ
ALT Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| Male, age 18+ | 7.00 – 55.0 U/L |
| Female, age 18+ | 7.00 – 45.0 U/L |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
What your ALT result may mean
Often reflects fatty liver, alcohol use, viral hepatitis, or muscle injury. Some medications also raise ALT.
What a high ALT means: causes, symptoms, next steps →Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
How do you get a ALT test?
Order online, a licensed physician reviews the requisition, and you walk into a nearby lab for the draw. ALT is available on its own or inside these panels — panels cost less per marker when you want the fuller picture.
| Option | Includes | Price |
|---|---|---|
| Comprehensive Metabolic Panel | This marker only | $22.99 |
| Gout Panel | 3 tests | $62.99 |
| Kidney Health Panel | 4 tests | $64.99 |
| General Wellness Panel | 4 tests | $89.99 |
| Post-COVID Recovery Panel | 7 tests | $99.99 |
Quest vs. Labcorp for ALT: which lab should you pick?
Both are CLIA-certified national labs and the result is clinically equivalent, so pick whichever location is closer. Your report will print that lab's own reference range, which can differ slightly from the table above.
| Lab | Available | Price |
|---|---|---|
| Quest Diagnostics | Yes | $22.99 |
| Labcorp | Yes | $22.99 |
| BioReference (NY & NJ) | Yes | $25.99 |
Need help choosing a location? Use the lab finder to see draw sites near your ZIP.
Related Metabolic Health biomarkers
Markers commonly tested alongside ALT.
Frequently asked
Often reflects fatty liver, alcohol use, viral hepatitis, or muscle injury. Some medications also raise ALT. A single result above the reference range is a prompt to look closer with a clinician — often a repeat test and related markers — not a diagnosis on its own.
Ready to test your alt?
Order in two minutes, get physician-approved, and visit a lab the same day. Starts at $22.99.