Accuracy Calculator — % Recovery & %RSD for Different % Spike Levels
Professional accuracy (recovery study) calculator for HPLC and UV-Vis assay validation. Enter your standard injections, standard weight and dilution factor, then your spiked sample data for each level — instantly get Recovered Amount, % Recovery, per-level mean & %RSD, and an overall mean recovery with pass/fail verdict against your chosen acceptance criteria. Add or remove spike levels and replicates freely to match your method SOP. Includes a recovery chart, full step-by-step math log, printable calculation sheet, and a built-in Beginner Tips & Guide tab.
Accuracy method: Inject your standard solution 5–6 times to establish the average standard area, then prepare and analyze spiked sample solutions at % Spike levels of the label claim (or as required by your method SOP) in triplicate. The calculator computes % Recovery for each replicate, the mean & %RSD for each level, and the overall mean recovery — then checks both against your chosen acceptance criteria.
Instrument Type
Updates the response label everywhere below — table, results, chart & print report. UV-Vis also enforces a valid 0.00–2.00 AU absorbance range.
Step 1 — Standard Injections (System Suitability)
Enter the peak area of each standard injection (typically 5). These are averaged to give the reference value used in every recovery calculation below.
No.
Area of Standard
Standard Injections: Count = 0 | Avg. Std Area = 0.00 | SD = 0.00 | % RSD = 0.00%(limit ≤ 2% per USP <621>)
Step 2 — Standard Weight & Dilution Factor
Weight of working/reference standard used to prepare the standard solution
Multiply your stepwise dilution ratios, e.g. 1/200 × 200/1 × 50/5 = 10
Optional correction factor (e.g. potency/purity factor). Leave blank to skip — it only appears in the formula and calculation when a value is entered.
Controls displayed digits only — does not affect calculation accuracy
Step 3 — Acceptance Criteria
Overall mean % Recovery must fall within this range
Each spike level's %RSD must fall at or below this limit
Updates every heading below, results and the printed report
Step 4 — Spike Levels & Replicate Data
Each level below is its own mini calculation table — just like your paper/Excel calculation sheet. Add or remove levels and replicate rows freely.
✅
Accuracy Passed
Overall mean recovery and per-level %RSD fall within the acceptance criteria.
Overall Mean % Recovery
-
Pooled across all levels & replicates
Overall % RSD
-
Pooled relative standard deviation
Avg. Standard Area
-
From standard injections
Valid Data Points (n)
-
Total replicates used
📊 Level Summary
Mean % Recovery & %RSD per Spike Level — Accuracy (Assay)
Level
Conc. (%)
n
Mean % Recovery
% RSD
📈 Recovery Chart
% Recovery by Spike Level
Individual Replicates vs Acceptance Band
🔢 Mathematical Log
Step-by-Step Calculation Trace
1
Step 1 — Average Standard Area
Average the standard injection areas to get the reference area used below:
Worked example using the first valid replicate entered:
3
Step 3 — Per-Level Mean & %RSD
Each level's % Recovery values are averaged and their spread checked:
4
Step 4 — Overall Mean Recovery & %RSD
All valid % Recovery values (across every level) are pooled together:
⚠️ Disclaimer
BestPharmaTools.com provides this Accuracy Calculator strictly for educational and informational purposes. It is an independent, unaffiliated online tool and is not a validated laboratory instrument, controlled GMP document, or a substitute for your organization's approved Quality Management System, Standard Operating Procedures, or review by qualified QA/QC personnel. All data entered is provided solely by the user; BestPharmaTools.com does not verify, endorse, or take responsibility for its accuracy, completeness, or suitability for any regulatory, clinical, or commercial use. Any output — including results viewed, copied, or printed — is used entirely at the user's own discretion and risk. BestPharmaTools.com and its owners/affiliates accept no liability for any decisions, actions, losses, or damages arising from use of this tool. Always verify calculations independently and follow your organization's validated systems and approved SOPs for any official, regulatory, or GMP-related documentation.
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