Biology & Genetics

Dilution Factor Calculator

Calculate dilution factor and the cumulative dilution after any number of serial steps.

mL
mL
Dilution factor per step
Factor = (stock + diluent) ÷ stock; serial dilution = factor^stepsStock volumemLDiluent volumemLSerial stepsvalue

Three 1:10 steps give 1:1000, not 1:30

Serial dilutions multiply rather than add. That is the whole reason the technique exists: reaching 1:1000 in one step would mean one millilitre of stock in a litre of diluent, and the pipetting error at that scale swamps the result.

What this page needs from you

This page asks for stock volume in mL, diluent volume in mL and serial steps. From those it returns dilution factor per step in ×, together with final dilution after all steps, concentration remaining, total volume per step and steps to reach 1:1,000,000. Every figure updates as you type, and nothing you enter leaves your browser.

Reproducibility depends on the inputs

The arithmetic here is exact; the measurements feeding it usually are not. Pipetting error, incomplete mixing and drift in a spectrophotometer all propagate straight through. Where a result matters, run it in duplicate and compare rather than trusting a single reading.

The formula

Factor = (stock + diluent) ÷ stock; serial dilution = factor^steps

Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.

How to use the Dilution Factor Calculator

  1. Fill in each field with your own figures — the defaults are only there as an example.
  2. The result updates as you type, so there is no button to press.
  3. Check the breakdown under the main result for the supporting numbers.
  4. Use the copy button to take the result with you, or share the link to reload the same inputs.

Dilution Factor Calculator — frequently asked questions

Is this dilution factor calculator free to use?

Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.

How accurate is the result?

The maths is exact for the formula shown on the page. Accuracy in the real world depends on your inputs and on assumptions the formula cannot see, so treat the output as a well-grounded estimate rather than a quote.

Can I use it on my phone?

Yes. The page is responsive, weighs a few kilobytes and works offline once loaded, so it behaves the same on a phone as on a desktop.

What people search for

This page answers each of these searches. They are the exact phrases visitors use to find the dilution factor calculator.

  • dilution factor calculator
  • how to do a serial dilution
  • dilution ratio calculator
  • 1 in 10 dilution

About this calculator

Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.

Last reviewed September 14, 2026 · Calculation runs client-side · No data collected · Report an error