Read Write Quorum Calculator
Calculate replica-set intersection guarantees and simple unavailable-replica bounds.
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Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Apply set intersection bounds to acknowledgements drawn from one fixed replica set.
Minimum read/write intersection=max(0,R+W−N); write/write=max(0,2W−N)
Worked example
N=5,R=3,W=3 guarantees at least one common read/write replica.
Assumptions and input details
Requires R,W≤N. Intersection alone does not establish linearizability: ordering, failures, membership, version reconciliation and protocol details matter. No systems are accessed or configured.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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