Primer Annealing Temperature Calculator

Primer Annealing Temperature Calculator: Calculate PCR Primer Ta

Calculate the annealing temperature (Ta) for a DNA primer used in PCR. Input your DNA primer sequence (using A, T, C, G) using the keypad or keyboard, then click Calculate to get the Ta in degrees Celsius.

How It Works

Enter your DNA primer sequence using the keypad or keyboard, then click “Calculate” to see the annealing temperature. The calculator displays the total sequence length and Ta (°C). Use the “Share” button to copy the calculator’s URL or the “Embed” button to copy an iframe code for embedding on another website.

Primer Annealing Temperature Calculator

DNA Primer Sequence

Result

Total Sequence Length:

Melting Temperature (°C):

Annealing Temperature (°C):

Steps

About Primer Annealing Temperature Calculator

The Primer Annealing Temperature Calculator computes the annealing temperature (Ta) for a DNA primer used in PCR, which is the temperature at which the primer binds to the template DNA. It’s a critical tool for optimizing PCR experiments in molecular biology research.

How to Use

  • Enter your DNA primer sequence using the keypad buttons (A, T, C, G) or keyboard (case-insensitive).
  • Click the “Calculate” button to compute the Ta. The page will scroll to the result.
  • Click the “Clear” button to reset the sequence input and results.
  • Click the “Share” button to copy the calculator’s URL to your clipboard for sharing.
  • Click the “Embed” button to copy an iframe code for embedding the calculator on another website.
  • The total sequence length, Tm (°C), and Ta (°C) will be displayed, along with detailed step-by-step calculations below.

Formulas

Melting Temperature (Tm):

Tm (°C) = 2 × (A + T) + 4 × (G + C)

Annealing Temperature (Ta):

Ta (°C) = Tm – 5

Important Notes

  • The sequence must contain only valid nucleotides: A, T, C, G (case-insensitive). Invalid characters or empty sequences will trigger an error.
  • The Tm is calculated using the Wallace rule, suitable for short sequences (≤50 bases) under standard conditions (50 mM Na+).
  • The Ta is estimated as Tm – 5°C, a common approximation for PCR primers.
  • The “Share” and “Embed” buttons require a browser that supports the Clipboard API.