GIFSQ Tools · Module 1 — Food Composition & Proximate Analysis · Tool 18 of 500
Correct a measured concentration back to the original sample. Enter the measured value and either the dilution factor or the aliquot and final volumes.
Try sample values — fills the form with the worked example below.
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Corrected concentration
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Dilution factor
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Measured concentration
Equation: Dilution factor = final volume ÷ aliquot volume (where volumes are given)
Corrected concentration = measured concentration × dilution factor.
Method: Serial dilution practice, FDA Bacteriological Analytical Manual (BAM) Chapter 3 and AOAC dilution guidance — the dilution factor is the ratio of the final volume to the volume taken.
Assumptions: the dilution was made up exactly to the final volume; the measured value sits inside the method's working range.
Limitations: a factor below 1 means the sample was concentrated, not diluted — check the volumes; the correction does not fix a measurement taken outside the calibration range.
Rounding: results to 2 decimal places; intermediate values are not rounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Corrected concentration = measured concentration × dilution factor.
Method: Serial dilution practice, FDA Bacteriological Analytical Manual (BAM) Chapter 3 and AOAC dilution guidance — the dilution factor is the ratio of the final volume to the volume taken.
Assumptions: the dilution was made up exactly to the final volume; the measured value sits inside the method's working range.
Limitations: a factor below 1 means the sample was concentrated, not diluted — check the volumes; the correction does not fix a measurement taken outside the calibration range.
Rounding: results to 2 decimal places; intermediate values are not rounded.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Worked example: Measured 2.50 mg/L after a 10-fold dilution. Corrected concentration = 2.50 × 10 = 25.00 mg/L. From volumes: 10.00 mL made up to 100.00 mL gives a factor of 100 ÷ 10 = 10.00, so 0.80 mg/L measured corrects to 8.00 mg/L.
Enter values above to see results.
Give the factor directly, or give both volumes — if both are given, the volumes win and the factor is checked against them. A factor of 1 means no dilution. Tool 18 of 500 — GIFSQ
