biology Calculators
Last updated: May 2026
Mitotic Index Calculator
Compute the mitotic index — the fraction of cells actively dividing — from the count of mitotic cells and the total cell count, expressed as a percentage.
Hardy-Weinberg Equilibrium Calculator
Verify the Hardy-Weinberg equilibrium identity p² + 2pq + q² = 1 from two allele frequencies.
Protein Concentration Calculator
Compute protein concentration from absorbance at 595 nm using a linear standard curve.
Population Growth Rate Calculator
Compute the exponential growth rate r from initial and final population sizes over a time interval, as r = ln(N_final / N_initial) / t.
DNA Concentration Calculator
Estimate double-stranded DNA concentration from absorbance at 260 nm using the standard 50 μg/ml per A260 conversion.
Enzyme Activity Calculator
Compute enzyme activity in U/mL from the rate of absorbance change in a spectrophotometric assay using the Beer-Lambert law.
PCR Efficiency Calculator
Compute the amplification efficiency of a qPCR reaction from the slope of a standard curve fitting Cq values against the log of template concentration.
Cell Density Calculator
Estimate cell concentration in cells/mL from a haemocytometer count using cellCount, the number of squares counted, and the dilution factor.
Genetic Distance Calculator
Compute the genetic map distance between two linked loci in centimorgans (cM) from the recombination frequency observed in offspring.
Shannon Diversity Index Calculator
Compute the Shannon (Shannon-Wiener) diversity index H' for three species from their abundance counts.
Gene Expression Fold Change Calculator
Quantify how much a gene is up- or down-regulated between two conditions using the 2^(−ΔΔCt) method from qRT-PCR data.
Allele Frequency Calculator
Compute the frequency of a specific allele in a population from counts of each genotype (AA, Aa, aa).
Chromosome Map Distance Calculator
Convert recombination frequency into genetic map distance in centimorgans (cM) between two loci on a chromosome.
Cell Surface Area to Volume Ratio Calculator
Calculate the surface area to volume ratio (SA:V) of a spherical cell given its radius.
Mutation Rate Calculator
Calculate the mutation rate per generation per individual from observed mutation counts across a population over multiple generations.
Buffer Capacity Calculator
Determine how well a buffer solution resists pH changes by entering its concentration, pKa, and target pH.
Photosynthesis Rate Calculator
Measure the rate of photosynthesis in a plant sample by entering the volume of oxygen produced, the duration of the experiment, and the plant's mass.
Primer Melting Temperature Calculator
Estimate the melting temperature (Tm) of a PCR primer from its GC content and length using the simplified Wallace-rule approximation.
Metabolic Rate Calculator
Calculate mass-specific metabolic rate from an organism's oxygen consumption, body mass, and respiratory quotient.
DNA GC Content Calculator
Calculate the percentage of guanine and cytosine bases in a DNA sequence by entering nucleotide counts.
Protein Molecular Weight Calculator
Estimates the molecular weight of a protein from its amino acid count and average residue mass.
PCR Primer Tm Calculator
Calculates the melting temperature (Tm) of short PCR primers using the Wallace rule base-counting method.
Bacterial Generation Time Calculator
Determines how long bacteria take to double in number during exponential growth.
Chlorophyll Concentration Calculator
Converts spectrophotometer absorbance readings at 645 nm and 663 nm into total chlorophyll concentration in a plant extract.
Shannon Diversity Index Calculator
Computes the Shannon diversity index (H′) from the individual counts of up to three species in an ecological community.
Gene Expression Fold Change Calculator
Determine how much a gene is up- or down-regulated by dividing treatment expression by control expression.
Surface Area to Volume Ratio Calculator
Calculates the surface area to volume ratio of a spherical cell given its radius.
Protein Extinction Coefficient Calculator
Estimates a protein's molar extinction coefficient at 280 nm from its tryptophan, tyrosine, and cysteine residue counts.
Leaf Area Index Calculator
Computes the Leaf Area Index (LAI) by dividing total one-sided leaf area by the ground surface area beneath a plant canopy.
Cardiac Output Calculator
Calculates cardiac output in liters per minute from heart rate (bpm) and stroke volume (mL).
Photosynthetic Rate Calculator
Calculate a leaf's photosynthetic rate from CO₂ uptake measurements.