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PCR, qPCR & Molecular Biology

Entered-Efficiency PCR Cycle Model Workbench

Propagate an entered starting-copy scenario through a declared number of cycles with one constant per-cycle amplification efficiency and retain a cycle ledger.

Biology · experimental measurements

Separate ideal doubling, an entered constant-efficiency scenario and actual endpoint yield instead of presenting an exponential model as a laboratory forecast.

Private calculations in your browser · explicit inputs and model boundaries
Example preview · Ideal doublingModeled copy accumulation by cycle
002.62e655.24e6107.86e6151.05e720100% entered efficiencyIdeal doublingCycleModeled copies
100% entered efficiencyIdeal doubling

The entered-efficiency and ideal-doubling curves begin at the same starting amount. Their divergence reflects only the two declared constant factors.

  1. 1EnterProvide the known values
  2. 2CalculateResults update automatically
  3. 3VerifyReview the details and units
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Enter values in %.

Calculation result

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Understand the relationship

The reasoning behind the result

Efficiency is a fractional gain per cycle

Nn = N₀(1 + η)ⁿ

At η=1 the amount doubles; at η=0 it remains constant.

A single η assumes the same fractional gain in every modeled cycle.

The gap compounds

entered/ideal = [(1+η)/2]ⁿ

A modest per-cycle difference can produce a large endpoint difference.

That sensitivity makes an unvalidated efficiency unsuitable as a yield forecast.

Endpoint chemistry is not exponential forever

Reagent depletion, product reannealing, inhibition and instrument thresholds can change efficiency across cycles.

Low-copy sampling and molecular loss are stochastic and absent from this deterministic expectation.

Follow the numbers

Propagate an 85% efficiency scenario

  1. Convert 85% to η=0.85.
  2. Use the per-cycle factor 1.85.
  3. Raise 1.85 to 30 cycles and multiply by the 100 entered starting copies.
  4. Compare with the separate ideal factor 2³⁰.

The modeled endpoint belongs only to a constant-efficiency exponential scenario.

Quick guide

How to use this calculator

  1. Enter a starting-copy scenario rather than a fluorescence reading.
  2. Use an efficiency that belongs to the declared model or measured exponential region.
  3. Treat the result as exponential arithmetic; inspect actual reaction data for baseline, inhibition, plateau and uncertainty.

Calculation method

Calculation and interpretation

Separate ideal doubling, an entered constant-efficiency scenario and actual endpoint yield instead of presenting an exponential model as a laboratory forecast.

Modeled copies after n cycles = N₀(1 + η)ⁿ, where η is the visitor-entered fractional efficiency; ideal comparison = N₀2ⁿ.

Worked example

Propagate an 85% efficiency scenario

The modeled endpoint belongs only to a constant-efficiency exponential scenario.

Modeled copies after n cycles = N₀(1 + η)ⁿ, where η is the visitor-entered fractional efficiency; ideal comparison = N₀2ⁿ.

Supported inputs

Precision and limits

Constant efficiency

One entered efficiency applies to every modeled cycle; cycle-varying kinetics are not fitted.

Deterministic expectation

Starting-copy sampling, dropout, molecular loss and replicate uncertainty are not simulated.

No plateau

Reagent depletion, product inhibition and endpoint saturation are outside the equation.

No fluorescence conversion

The workbench does not infer copies from Cq, RFU, baseline or threshold settings.

Computational range

Whole cycle counts from 0–1,000 and efficiencies from 0–100% are accepted when the resulting finite copy count remains representable.

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