pKa Calculator
⚖ Acids, Bases & Equilibrium. Use the pKa formula to find pka, ka: pick the value you want, type the others, and the answer updates as you go.
pKa4.7595
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| pKa | no unit |
| Ka | no unit |
Worked example
Find the pka when Ka = 1.74 × 10⁻⁵.
Using pKa = -log Ka: pKa = 4.7595.
Frequently asked questions
What is the formula for pKa?
pKa = -log Ka.
What do the letters stand for, and what units are used?
pKa, Ka.
How do you calculate pka?
Put the values into pKa = -log Ka. For example, with Ka = 1.74 × 10⁻⁵, pka = 4.7595.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (pka, ka) and fill in the others: it rearranges the formula for you.
