Stock dilution
Stock and diluent volumes from C₁V₁ = C₂V₂.
What this calculator does
Calculate stock and diluent volumes for a working solution with C1V1 = C2V2, in molar, mass or fold units, with optional pipette setpoint checks.
Calculation model
Mass balance, C₁·V₁ = C₂·V₂ (forward and reverse problems) + setpoint audit
Formulas
- F01 · Stock dilution:
C₁·V₁ = C₂·V₂;V_stock = C_target · V_final / C_stock;V_diluent = V_final − V_stock - P01 · Direct working dilution:
C_source · V_source = C_working · V_prepared;DF = C_source / C_working = V_prepared / V_source;V_diluent = V_prepared − V_source - P02 · Stock + diluent notation:
a + b = a parts stock + b parts diluent;DF = (a + b) / a; 1 + 9 = 1:10; 10 + 190 = 1:20 - P04 · Prepared concentration after setpoint rounding:
C_working,planned = C_source · V_stock,planned / (V_stock,planned + V_diluent,planned);achieved DF = (V_stock + V_diluent) / V_stock (not the requested DF if rounded) - P08 · Instrument setpoint quantization:
setpoint_nL = round(V · 1000 / increment_nL) · increment_nL (nearest | down | up);settable ⇔ range_min ≤ setpoint ≤ range_max; increment ≠ accuracy
Assumptions
- Volumes are additive and solutions homogeneous.
- No reaction between solute and diluent.
- Stock and target must use the same kind of concentration unit (molar, mass or fold).
Verification status
- tests-passed means automated algorithm tests (unit, property, integration and browser end-to-end) pass. It is not an independent scientific review and not laboratory validation.
References
- [S01] NEB: NEBioCalculator (DNA, ligation, OD260, dilution and molarity calculators) (accessed 2026-10-29)
- [S04] IDT: Oligo Resuspension and Dilution Calculators (accessed 2026-10-29)
- [EP01] Eppendorf: Research plus technical data (DE): ranges, increments, published test-point deviations. Pinned dataset; live page not re-verified (HTTP 403, 2026-10-29) (accessed 2026-10-29)
- [R2SPEC] Project: docs/RELEASE_2_INTELLIGENT_PREPARATION_SPEC.md v1.0 (2026-10-29): preparation model and recommendation rules (proposed specification, not validation evidence)
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