Unit Converter

When you actually need a unit converter

Most published veterinary doses come in mg/kg. Most drug labels come in mg/mL, percent, or ratio. The vial in your hand is rarely already in the unit your protocol expects. A unit converter that handles the common veterinary edge cases — ratios like 1:1000 epinephrine, percent labels like 2% lidocaine, owner- reported pet weights in pounds — saves the four or five mental conversions per medication you'd otherwise carry under time pressure.

The converter handles three categories: mass (mcg ⇄ mg ⇄ g, the everyday dose unit), patient weight (kg ⇄ lb, since most owners report in pounds), and concentration (percent ⇄ mg/mL and ratio ⇄ mg/mL, the two label conventions you encounter on emergency drugs and topicals).

Percent ⇄ mg/mL — the conversion that catches everyone

A 1% solution is 1 g per 100 mL, which is 10 mg/mL. The shortcut: multiply percent by 10 to get mg/mL. Lidocaine 2% is 20 mg/mL. Dextrose 50% is 500 mg/mL. Calcium gluconate 10% is 100 mg/mL. The math is trivial once you internalise it; the error mode is forgetting it in the middle of a code and reaching for the calculator.

Ratio ⇄ mg/mL — the epinephrine convention

Epinephrine is labelled by ratio: 1:1000 is the common code-cart vial (the high-concentration form for IM/SC), 1:10,000 is the diluted code dose used IV. The conversion:

• 1:1000 = 1 g in 1,000 mL = 1 mg/mL.
• 1:10,000 = 1 g in 10,000 mL = 0.1 mg/mL.
• 1:100,000 = 1 g in 100,000 mL = 0.01 mg/mL.

Practical implication: a 10-kg dog gets 0.01 mg/kg IV during CPR = 0.1 mg total. That's 0.1 mL of the 1:1000 vial (1 mg/mL) or 1.0 mL of the 1:10,000 dilution. The two volumes are tenfold apart; pulling the wrong-concentration vial without converting is exactly the decimal mistake the RECOVER initiative flags.

Kg ⇄ lb — owner reports and per-pound rules

1 kg = 2.2046 lb. For clinical work, 1 kg ≈ 2.2 lb is precise enough — a 22-lb dog is 10 kg, a 5.5-lb cat is 2.5 kg. The converter handles arbitrary decimals when the owner reports a fractional pound weight from a home scale.

Most published veterinary references are per-kg. A few US drug labels are per-pound; older Plumb's editions and some FDA-approved canine product labels show both. When a per-pound rule appears, double-check the conversion before dosing — a 5 mg/lb rule on a 10-kg dog is 22 lb × 5 mg = 110 mg, not 50 mg.

Mcg ⇄ mg ⇄ g — the order-of-magnitude trap

1,000 mcg = 1 mg. 1,000 mg = 1 g. Order-of-magnitude errors happen most often on CRI rates where the protocol is written in mcg/kg/min and the bag concentration is in mg/mL — a 1,000-fold conversion needs to happen and a missed decimal produces a dose 1,000-fold off. The CRI calculator carries the conversion automatically; the unit converter here is the standalone tool when you only need the conversion itself.

Worked examples

Concentration → dose volume

A 2-kg cat needs 0.5 mg/kg of dexmedetomidine. Vial concentration is 0.5 mg/mL.

• Total dose: 0.5 mg/kg × 2 kg = 1.0 mg.
• Volume to draw: 1.0 mg ÷ 0.5 mg/mL = 2.0 mL.

Percent label → mg dose

A 25-kg dog needs 2 mg/kg lidocaine slow IV for a ventricular arrhythmia. The vial is labelled 2%.

• Convert: 2% = 20 mg/mL.
• Total dose: 2 mg/kg × 25 kg = 50 mg.
• Volume: 50 mg ÷ 20 mg/mL = 2.5 mL.

Ratio label → mg dose

A 10-kg dog in CPA needs 0.01 mg/kg epinephrine IV. The crash- cart vial is 1:1000.

• Convert: 1:1000 = 1 mg/mL.
• Total dose: 0.01 mg/kg × 10 kg = 0.1 mg.
• Volume: 0.1 mg ÷ 1 mg/mL = 0.1 mL drawn from the 1:1000 vial.

Note that the 1:10,000 dilution (used by some protocols for easier titration in small patients) would be 1.0 mL for the same patient — same dose, ten times the volume. The emergency dose chart pre-computes both routes per weight.

Frequently asked questions

Does this converter work offline?

Yes — the conversions run entirely in the browser. Once the page has loaded, no connection is needed.

Why convert ratio at all — isn't mg/mL clearer?

Yes, it is. But epinephrine and a few legacy emergency drugs still ship with ratio labels in many markets, and older protocols (and some non-English references) still refer to them by ratio. Knowing the conversion is a defensive skill.

What about IU and other biological-activity units?

Not handled by this tool — IU conversions are drug-specific (insulin, oxytocin, heparin all have different IU-to-mass relationships). The drug page for each will carry the conversion if one is needed.

Does the calculator round its outputs?

The converter shows the unrounded answer; round to your clinical convention before dosing. For most clinical volumes, two significant figures is reasonable (0.1 mL, 2.5 mL, 12 mL). Sub-milliliter volumes below 0.1 mL usually warrant dilution before drawing — accuracy with a standard syringe drops below 0.05 mL.

Where do I find the per-mg dose ranges to plug in?

On the drug pages — browse the formulary for any drug, and each species-specific dose rule shows the citation. The converter handles the unit math; the drug page shows what the protocol calls for.

Reference only — not veterinary advice. See the full disclaimer.