Insulin Drip Titration Calculator: Units/h to mL/h and Pump-Rate Change
Convert an IV insulin infusion order between units/hour and mL/hour for any bag concentration, apply a titration step as a new rate, a percentage or a units/h change, and see the pump-rate change, units/kg/h, 24-hour insulin and how long the bag lasts.
How it works
mL/h = units per hour ÷ concentration (units/mL) · Concentration = units in bag ÷ bag volume (mL) · Percentage step: new units/h = current × (1 + % ÷ 100) · Change = new mL/h − current mL/h · units/kg/h = units/h ÷ weight · Bag lasts (h) = mL left ÷ mL/h
IV insulin is ordered in units per hour but delivered by a pump set in millilitres per hour, so the bag concentration links the two. At the common 1 unit/mL mix (100 units of regular insulin in 100 mL of 0.9% saline) the numbers are the same; any other mix must be converted by dividing the units/h by the units/mL. Insulin infusion protocols raise or lower the rate from hourly glucose readings, sometimes as a new rate, sometimes as a percentage or a fixed units/h step. Choose the type of step your protocol uses and the calculator shows the new pump rate, the size of the change and the matching table of rates. The optional weight shows the dose in units/kg/h, which is how diabetic ketoacidosis regimens are written. The 2024 international consensus on hyperglycaemic crises uses a fixed 0.1 units/kg/h for moderate or severe DKA (no routine bolus) and 0.05 units/kg/h for HHS, adds 5–10% dextrose once glucose falls below 250 mg/dL and then lowers the DKA rate to 0.05 units/kg/h until the ketoacidosis resolves. Older 2009 guidance also allowed 0.14 units/kg/h without a bolus and a reduced rate of 0.02–0.05 units/kg/h. The calculator does not decide the titration: the new rate always comes from the order or your institution's protocol, which takes precedence, and every change should be double-checked.
Worked example
With the defaults, 100 units in 100 mL (1 unit/mL): the current 2 units/h runs at 2 ÷ 1 = 2.00 mL/h. When the protocol raises the order to 3 units/h, the new pump rate is 3 ÷ 1 = 3.00 mL/h, an increase of 1.00 mL/h (+50% in dose), or 72 units over 24 hours; the 100 mL left in the bag lasts 33.3 hours. With a 0.5 unit/mL bag the same 3 units/h would be 6.00 mL/h.
Sources: Diabetic ketoacidosis: insulin infusion 0.1 units/kg/h (0.14 without bolus), rate reduction, dextrose and potassium thresholds (WikEM) · Hyperglycemic crises in adults: the 2024 consensus report (review with 2009 vs 2024 insulin rates, Cleveland Clinic Journal of Medicine) · NIH/NLM DailyMed — regular human insulin labeling
Frequently asked questions
How do I convert insulin units/h to mL/h?
Divide the units per hour by the concentration in units/mL. At 1 unit/mL (100 units in 100 mL) they are the same number; at 0.5 unit/mL, 4 units/h is 8 mL/h; at 2 units/mL it is 2 mL/h.
What concentration should I use?
Use the concentration of the prepared bag: total units divided by the volume in mL. The near-universal standard is 100 units in 100 mL, which is exactly 1 unit/mL, but always confirm the label rather than assuming.
Does this decide the titration for me?
No. The new units/h comes from your glucose-driven insulin infusion protocol or the prescriber; this calculator only converts that ordered rate to the mL/h to program and shows the change. Clinical decisions stay with the protocol and the provider.
What is the usual insulin drip rate in DKA?
The 2024 consensus report on hyperglycaemic crises in adults recommends a fixed 0.1 units/kg/h for moderate or severe DKA without a routine bolus. Once glucose falls below 250 mg/dL, 5–10% dextrose is added and the rate is lowered to 0.05 units/kg/h, continued until the ketoacidosis resolves. If potassium is below 3.5 mmol/L, insulin is postponed until replacement brings it above 3.5 mmol/L. Follow your institution's DKA protocol.
Why not just set the pump in units per hour?
Many volumetric pumps are programmed in mL/h, so the order must be converted with the concentration. Smart pumps with a drug library may accept units/h directly; even then, confirming the mL/h helps catch concentration errors.
Related calculators
Educational estimate only — not medical advice, and no substitute for a clinician, pharmacist or the product label. IV insulin is a high-alert medication: every rate change must come from the prescriber's order or your institution's insulin infusion protocol and be independently double-checked against the bag label, the pump and the patient. Institutional protocols take precedence over this tool. Do not use it to self-treat or to bypass a double-check policy.