pH Calculator (pH/pOH/Concentration Conversion)
A simple pH calculator to convert between pH, pOH, and [H+]. Useful for study, lab notes, or quick checks.
pH calculator / pOH calculator / hydrogen ion concentration to pH.
Eingabe
EingabemodusThis tool uses a base value (pKw=14.00). Exact values change with temperature.
Applied to [H+], [OH-]
Show formula + substitution
Detailed settings
Default is 2 decimal places
Beispiele
Inputs are processed locally in your browser.
Results (set of 4)
- pH
- —
- pOH
- —
- [H+] (mol/L)
- —
- [OH-] (mol/L)
- —
Assumptions: pKw=14.00 (around 25°C) / activity coefficient = 1.
Assumptions (scope of this tool)
• This is a basic conversion from concentration to pH (activity not included).
• Water ion product (pKw) and neutrality shift with temperature.
• Errors increase for high concentration or high ionic strength solutions.
Häufige Beispiele
Häufig gestellte Fragen (FAQ)
Does temperature change the result?
Yes, strictly. This tool uses a base value (pKw=14.00) and shows temperature as a note only.
What about buffers?
Buffers require a different model (Henderson–Hasselbalch). See related tools.
Is this accurate enough for research?
This is for quick estimates. Use calibrated measurements and activity corrections for research or QC.
What unit is [H+]?
mol/L (M) is assumed in this tool.
Is pH + pOH always 14?
14 is a common base value near 25°C, but pKw changes with temperature. This tool uses 14 for basic calculation.
Wichtige Hinweise
• This tool is for education and field notes only.
• Temperature, activity (concentration ≠ activity), and ionic strength can cause deviations from measured values.
• For research or QC, use calibrated pH meters and condition-specific corrections.