Direct comparison
Isopropyl Alcohol vs Ethanol: Key Differences
Isopropyl alcohol vs ethanol side by side using NIOSH and CDC data: flash point, flammable range, exposure limits, virus coverage and rubbing alcohol.
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How do Isopropyl alcohol, Ethanol compare side by side?
The table below compares Isopropyl alcohol, Ethanol across 11 procurement-relevant dimensions, from other names (niosh pocket guide) through source.
Side-by-side comparison
| Dimension | Isopropyl alcohol | Ethanol |
|---|---|---|
| Other names (NIOSH Pocket Guide) | Isopropanol, 2-propanol, IPA, dimethyl carbinol, sec-propyl alcohol, rubbing alcohol | Ethyl alcohol, ethanol, EtOH, grain alcohol, cologne spirit |
| CAS number and molecular weight | CAS 67-63-0; molecular weight 60.1 | CAS 64-17-5; formula CH3CH2OH; molecular weight 46.1 |
| Flash point | 53 F | 55 F (NIOSH lists ethanol as a Class IB flammable liquid) |
| Boiling point and vapor pressure | 181 F; 33 mmHg | 173 F; 44 mmHg |
| Flammable range in air (LEL to UEL) | 2.0% to 12.7% (UEL at 200 F). CDC: alcohols are flammable and must be stored in a cool, well-ventilated area | 3.3% to 19%. CDC: alcohols are flammable and must be stored in a cool, well-ventilated area |
| Airborne exposure limits (inhalation) | NIOSH REL 400 ppm TWA (980 mg/m3), 500 ppm short-term (1225 mg/m3); OSHA PEL 400 ppm TWA; IDLH 2000 ppm [10% LEL] | NIOSH REL 1000 ppm TWA (1900 mg/m3); OSHA PEL 1000 ppm TWA; IDLH 3300 ppm [10% LEL] |
| Disinfectant concentration (CDC) | Optimum bactericidal concentration is 60%-90% in water (v/v); activity drops sharply below 50% | Same 60%-90% (v/v) optimum band; absolute (undiluted) ethanol is less bactericidal than alcohol-water mixtures |
| Virus coverage (CDC) | Not active against the nonlipid enteroviruses | At 60%-80%, a potent virucidal agent |
| What neither does (CDC) | Does not destroy bacterial spores; lacks sporicidal action, so not for sterilizing medical or surgical materials | Does not destroy bacterial spores; lacks sporicidal action, so not for sterilizing medical or surgical materials |
| When to pick each | Choose by the product label and safety data sheet for the task. Where the question is activity against nonlipid enteroviruses, CDC says isopropyl alcohol is not active against them. Where the question is airborne exposure, its limits are lower than ethanol's. | Choose by the product label and safety data sheet for the task. Where the question is virucidal activity, CDC describes 60%-80% ethanol as a potent virucidal agent. Where the question is flammable range, ethanol's is wider (3.3%-19%). |
| Source | CDC NIOSH Pocket Guide, Isopropyl alcohol (https://www.cdc.gov/niosh/npg/npgd0359.html); CDC Disinfection and Sterilization Guideline, Chemical Disinfectants: Alcohol (https://www.cdc.gov/infection-control/hcp/disinfection-sterilization/chemical-disinfectants.html). Read 2026-10-29. | CDC NIOSH Pocket Guide, Ethyl alcohol (https://www.cdc.gov/niosh/npg/npgd0262.html); CDC Disinfection and Sterilization Guideline, Chemical Disinfectants: Alcohol (https://www.cdc.gov/infection-control/hcp/disinfection-sterilization/chemical-disinfectants.html). Read 2026-10-29. |
Common questions
Common questions about Isopropyl alcohol vs Ethanol
Is isopropyl alcohol and rubbing alcohol the same?
+
In the NIOSH Pocket Guide, "rubbing alcohol" is listed as a synonym of isopropyl alcohol (isopropanol, 2-propanol, CAS 67-63-0). Ethanol (CAS 64-17-5) is a different compound whose listed synonyms are grain alcohol and EtOH. A product sold as rubbing alcohol names its active ingredient on the label, so read the label and safety data sheet for the ingredient and concentration. Our guide What Is Isopropyl Alcohol? covers the product concentrations.
Is isopropyl alcohol the same as rubbing alcohol?
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Per the NIOSH Pocket Guide, rubbing alcohol is a listed synonym of isopropyl alcohol, so the two names refer to the same compound. It is not the same as ethanol: the two have different CAS numbers (67-63-0 and 64-17-5), molecular weights (60.1 and 46.1) and exposure limits (400 ppm and 1000 ppm TWA).
Which is the stronger disinfectant, isopropyl alcohol or ethanol?
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CDC gives both alcohols the same optimum bactericidal band of 60%-90% in water by volume, so concentration matters more than which alcohol it is. They differ in virus coverage: CDC describes ethanol at 60%-80% as a potent virucidal agent and says isopropyl alcohol is not active against nonlipid enteroviruses. Neither destroys bacterial spores.
Going deeper
