Enter Dilution Details
Formula Used
The calculator first converts the stock strength from mg/mL to ug/mL.
Stock ug/mL = Stock mg/mL × 1000
It then applies the dilution equation.
C1 × V1 = C2 × V2
Here, C1 is the effective stock concentration. V1 is the stock volume needed. C2 is the target concentration. V2 is the final preparation volume.
V1 = (C2 × V2) ÷ C1
Diluent volume = Final volume − Stock volume
How to Use This Calculator
- Enter the stock concentration in mg/mL.
- Enter the required final concentration in ug/mL.
- Add the final volume and choose its unit.
- Set batch count if making several tubes.
- Add overage when extra working solution is needed.
- Adjust purity when the stock has an assay correction.
- Press calculate and read the result above the form.
- Download the result as CSV or PDF for records.
Example Data Table
| Stock mg/mL | Target ug/mL | Final Volume | Stock Needed | Diluent Needed | Dilution Factor |
|---|---|---|---|---|---|
| 10 | 100 | 10 mL | 0.100 mL | 9.900 mL | 1:100 |
| 5 | 250 | 20 mL | 1.000 mL | 19.000 mL | 1:20 |
| 2 | 50 | 25 mL | 0.625 mL | 24.375 mL | 1:40 |
| 1 | 10 | 50 mL | 0.500 mL | 49.500 mL | 1:100 |
Advanced Dilution Planning Guide
Why concentration conversion matters
A dilution plan needs matching units. Stock solutions are often labeled in mg/mL. Working solutions are often requested in ug/mL. One milligram equals one thousand micrograms. So a stock of 1 mg/mL equals 1000 ug/mL. This simple conversion prevents large preparation errors. It also makes the dilution equation easier to use.
Direct dilution from stock
This tool uses direct dilution. It assumes the target concentration is lower than the stock concentration. That is the normal dilution case. The calculator finds the stock volume first. Then it subtracts that amount from the final volume. The remaining volume is the diluent. The diluent may be water, buffer, solvent, or media.
Batch and overage planning
Many lab tasks require more than one tube. The batch count option multiplies the final volume. The overage option adds extra preparation volume. This helps when some liquid remains in tips, tubes, or reservoirs. A small overage can reduce shortages. Use a reasonable value. Ten percent is common for routine preparation. Larger values may waste expensive material.
Purity correction
Some stock labels show nominal concentration. The active amount may be lower. The purity field adjusts the usable stock strength. For example, a 10 mg/mL stock at 90 percent purity acts like 9 mg/mL. This correction increases the required stock volume. Leave purity at 100 percent when no correction is needed.
Pipette limits
Very small volumes can be hard to measure. The minimum pipette check warns you when stock volume is below your limit. This does not stop the calculation. It only warns you. If the warning appears, consider a serial dilution. A serial dilution can create an intermediate stock. That intermediate stock can make the final transfer volume easier to measure.
Reading the result
The main result shows stock volume and diluent volume. Both are shown in mL and uL. The dilution factor shows how much weaker the target is than the stock. A factor of 1:100 means one part stock in one hundred parts total final solution. The final mass line shows the amount of solute present in the prepared solution.
Good preparation habits
Always label tubes clearly. Include concentration, date, solvent, and initials. Use calibrated pipettes. Mix gently but fully. Check that the target is not stronger than the stock. This calculator cannot verify chemical stability or compatibility. Use your lab method, safety sheet, and supervisor guidance when preparing real samples.
FAQs
1. What does mg/mL to ug/mL mean?
It means converting milligrams per milliliter into micrograms per milliliter. Since 1 mg equals 1000 ug, multiply mg/mL by 1000.
2. What is the main dilution formula?
The main formula is C1V1 equals C2V2. It finds the stock volume needed for a target concentration and final volume.
3. Can this calculator plan a direct dilution?
Yes. It calculates direct dilution from a stronger stock solution to a weaker working solution.
4. Can dilution make a stronger solution?
No. Dilution only lowers concentration. If the target is stronger than the stock, a new stronger stock is required.
5. Why is the stock converted to ug/mL?
The target is entered in ug/mL. Matching units keeps the C1V1 equals C2V2 calculation correct and simple.
6. What is diluent volume?
Diluent volume is the amount of solvent, buffer, or media added after the stock volume. It completes the final volume.
7. What does dilution factor mean?
Dilution factor compares stock strength with target strength. A 1:100 dilution means the final solution is one hundred times weaker.
8. Why add overage?
Overage adds extra solution for handling loss. It helps when liquid remains in pipette tips, tubes, or reservoirs.
9. What is purity correction?
Purity correction lowers the effective stock concentration when the active material is less than 100 percent.
10. When should I use serial dilution?
Use serial dilution when the required stock volume is too small to pipette accurately or safely.
11. Can I use uL as the final volume unit?
Yes. Choose uL from the unit menu. The calculator converts it internally to mL for the formula.
12. Are CSV and PDF files available?
Yes. After calculation, use the download buttons to save the result as CSV or PDF.
13. Is ug the same as microgram?
Yes. The plain text form ug is commonly used when the micro symbol is not available.
14. Should I round the final volumes?
Round according to your pipette accuracy and lab method. Avoid rounding very small stock volumes too aggressively.