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Dilution Calculator
mg/mL

Calculate dilutions in milligrams per milliliter. Perfect for drug formulation, IV infusion preparation, and laboratory reagent dilution with mass-volume units.

5
Calc Modes
0ms
Solve Time
100%
Free Forever
C₁ × V₁ = C₂ × V₂
Leave one field blank to solve for it. Keep C₁ & C₂ in the same units.
C₁ Stock Concentration (initial)
SOLVING
V₁ Stock Volume (to take)
SOLVING
C₂ Final Concentration (desired)
SOLVING
V₂ Final Volume (total)
SOLVING
DF = C₁ ÷ C₂ = V₂ ÷ V₁
Enter stock & final concentrations. Optionally add volume for a recipe.
C₁ Stock Concentration
C₂ Final Concentration (same unit)
Final Volume (optional — for mixing recipe)
Stock : Diluent → Volumes
Enter parts stock, parts diluent, and total volume to make.
Parts Stock (the "1" in 1:10)
Parts Diluent (the "10" in 1:10)
Final Volume (total)
V₁ = (C₂ × V₂) ÷ C₁
Dilute a % stock to a target % — works for w/v, v/v, and w/w.
Stock Strength (% — higher value)
%
Target Strength (% — desired)
%
Final Volume Needed (total to make)
Cₙ = C₀ ÷ DFⁿ
Build a multi-step serial dilution series with a consistent dilution factor.
Starting Concentration (C₀)
Dilution Factor per Step (e.g. 10 for 1:10)
Number of Steps (tubes after stock)
Concentration Unit (label, optional)
⚠️ Error message here
Calculation Result
🧪 Overview

What Is a Dilution Calculator mg/mL?

A dilution calculator mg/mL solves C₁V₁ = C₂V₂ using mass-per-volume concentration units — the standard in pharmaceutical, clinical, and food science settings. Enter concentrations in mg/mL, µg/mL, or ng/mL and volumes in mL or µL to find the stock volume needed, the resulting concentration, or the total volume required. This covers drug formulation, IV preparation, and analytical standard dilution.

Benefits

  • Works directly with mg/mL — no molarity conversion needed
  • Calculates IV drug dilution for infusion preparation
  • Supports µg/mL and ng/mL for trace analysis
  • Shows diluent volume for reconstitution protocols
🔬

Applications

  • IV drug concentration adjustment in hospital pharmacy
  • Analytical standard preparation for HPLC and GC
  • Protein concentration dilution for Bradford or BCA assays
  • Pesticide residue standard preparation for EPA methods

Mass-volume concentration (mg/mL) eliminates the need to know molecular weight — unlike molarity. This makes mg/mL the preferred unit for complex mixtures, biologics, and polymers. Pharmaceutical manufacturers including Pfizer, Roche, and AbbVie express drug concentrations in mg/mL on vial labels. Analytical chemists preparing calibration standards for Agilent HPLC or Waters UPLC systems typically work in µg/mL. This mg/mL dilution calculator bridges both workflows.

📐 Core Equation

mg/mL Dilution Equation

The mg/mL dilution equation is identical to C₁V₁ = C₂V₂ — but with concentration expressed as mass per volume (mg/mL) instead of molarity. C₁ is the stock concentration in mg/mL, V₁ is the volume of stock taken, C₂ is the target concentration in mg/mL, and V₂ is the total final volume.

Interactive: Hover each variable to see its role
C₁ × V₁ = C₂ × V₂
C₁ = High conc. V₁ = Small vol.
Stock Solution
+ Diluent
C₂ = Low conc. V₂ = Large vol.
Final Solution
💡 The total amount of solute (C × V) is the same in both vessels — only the concentration changes.

Rearrange the equation to solve for any unknown:

V₁ = (C₂ × V₂) ÷ C₁— how much stock to pipette
C₂ = (C₁ × V₁) ÷ V₂— what concentration you'll get
V₂ = (C₁ × V₁) ÷ C₂— total volume needed

When working in mg/mL, you skip the molecular weight step entirely. A 10 mg/mL bovine serum albumin (BSA) stock diluted to 2 mg/mL uses the same formula: V₁ = (2 × V₂) ÷ 10. This is why protein assay standards from Bio-Rad and Thermo Fisher are supplied in mg/mL — it simplifies preparation across different proteins regardless of molecular weight.

🔢 Factor

mg/mL Dilution Factor

The dilution factor in mg/mL terms equals C₁ ÷ C₂. A 50 mg/mL stock diluted to 5 mg/mL has a factor of 10. For analytical standards, the dilution factor helps back-calculate the original sample concentration from the measured value.

DF = C₁ ÷ C₂ = V₂ ÷ V₁

Clinical laboratories running immunoassays on Roche cobas or Abbott Architect analyzers report results in ng/mL or µg/mL. When sample concentrations exceed the assay range, technicians dilute the sample and multiply the result by the dilution factor. This mg/mL dilution factor calculator handles the full range from ng/mL to g/mL.

Interactive: Click a factor to see the stock-to-diluent ratio
1 part stock
1 part diluent
Factor
Stock1 part
Diluent1 part
Total2 parts
📋 Step by Step

Step-by-Step Dilution Calculator mg/mL Guide

Follow these steps to calculate your dilution:

1
Record the stock concentration in mg/mL. Example: Vancomycin vial reconstituted to 50 mg/mL.
2
Identify the target concentration. Example: 5 mg/mL for IV infusion in 0.9% NaCl.
3
Set the final infusion volume. Example: 250 mL total volume for slow infusion.
4
Calculate stock volume needed. V₁ = (5 × 250) ÷ 50 = 25 mL of reconstituted drug.
5
Add diluent to reach final volume. Add 225 mL of 0.9% NaCl. Mix gently by inversion.
🔬 Serial Dilution

Serial Dilutions in mg/mL

Serial dilution in mg/mL is standard for creating calibration curves in analytical chemistry. A series of standards at 100, 50, 25, 12.5, 6.25, and 3.125 µg/mL covers the linear range of most UV-Vis spectrophotometry methods.

Cₙ = C₀ ÷ DFⁿ
C₀ = starting concentration · DF = dilution factor per step · n = step number
Interactive: Two-fold serial dilution from 1000 µM — hover each tube
Stock
1000 µM
Tube 1
500 µM
Tube 2
250 µM
Tube 3
125 µM
Tube 4
62.5 µM
16×
Tube 5
31.25 µM
32×
🧫 Each tube: Transfer a fixed volume → add diluent → mix → repeat. Concentration halves at every step.

Pharmaceutical quality control labs following ICH Q2(R1) validation guidelines prepare multi-point calibration curves by serial dilution of a certified reference standard. HPLC methods for assay and impurity testing from the USP require 5–7 calibration points. This mg/mL serial dilution calculator generates the exact concentrations and volumes for each point in the curve.

✏️ Worked Example

Dilution Calculator mg/mL Example

Problem: A pharmacist needs to prepare 100 mL of 1 mg/mL lidocaine from a 20 mg/mL stock for subcutaneous infiltration.

Step 1Identify variables
C₁ = 20 mg/mL (lidocaine stock)
C₂ = 1 mg/mL (target for infiltration)
V₂ = 100 mL (final volume)
V₁ = ? (stock volume to draw)
Step 2Rearrange formula
V₁ = (C₂ × V₂) ÷ C₁
Step 3Substitute values
V₁ = (1 × 100) ÷ 20 = 5 mL
Step 4Calculate diluent
Diluent = 100 − 5 = 95 mL
Step 5Verify
DF = 20 ÷ 1 = 20× dilution
Step 1 of 5
🧪
Recipe: Draw 5 mL of 20 mg/mL (2%) lidocaine using a sterile syringe. Inject into a 100 mL bag of 0.9% sodium chloride. Mix by gentle inversion. Label with: Lidocaine 1 mg/mL (0.1%), volume 100 mL, date, time, and preparer initials. Use within 24 hours per hospital pharmacy policy.
❓ FAQ

Frequently Asked Questions

Divide the mg/mL concentration by the molecular weight (g/mol), then multiply by 1000. Molarity (mM) = (mg/mL ÷ MW) × 1000. For example, 5 mg/mL glucose (MW 180.16): (5 ÷ 180.16) × 1000 = 27.75 mM. This mg/mL dilution calculator works directly in mg/mL, so molarity conversion is optional — use it only when protocols specify molar concentrations.

1% w/v = 10 mg/mL. Percent weight-per-volume means grams per 100 mL. A 1% solution contains 1 g per 100 mL = 10 mg per mL. To convert: mg/mL ÷ 10 = % w/v. A 50 mg/mL solution is 5% w/v. This mg/mL concentration calculator handles both notations.

Use V₁ = (C₂ × V₂) ÷ C₁. If the vial is 10 mg/mL and you need 2 mg/mL in 50 mL: V₁ = (2 × 50) ÷ 10 = 10 mL. Draw 10 mL from the vial, add to a 50 mL container, and fill to 50 mL with the appropriate diluent (sterile water, normal saline, or D5W per the drug monograph). Always verify compatibility from the package insert or Lexicomp database.