Test detection of digit substitutions.
Initialising algorithm engine for Single-Digit Error Simulator...
How Single-Digit Error Simulator Works?
The Single-Digit Error Simulator tests each possible digit change in a payload. It replaces each digit with every other digit and calculates the check character again. It counts the changes that produce a different result.
- 1Enter a payload and select the algorithms to test.
- 2Generate every single-digit substitution (9 per position).
- 3Recompute the check character for each altered payload.
- 4Count the substitutions that change the check character as detected.
- 5Report the detection rate per algorithm.
Single-Digit Error Simulator Formula
The detection rate formula is Rate = detected substitutions ÷ (9 × payload length) × 100%.
Tests = { payload with position i set to d | d ≠ original digit }
Rate = |{ t ∈ Tests : f(t) ≠ f(payload) }| ÷ |Tests| × 100%9 × lengthis the number of substitutions.
Substitutions tested = 90 Detected = 90 Rate = 100.0%
Single-Digit Error Simulator Conversion Table
The simulator table shows single-digit detection for 6 algorithms on the payload 7992739871.
| Algorithm | Substitutions | Detected | Missed | Detection rate |
|---|---|---|---|---|
| Luhn (Mod 10) | 90 | 90 | 0 | 100.0% |
| GS1 Mod 10 | 90 | 90 | 0 | 100.0% |
| Verhoeff | 90 | 90 | 0 | 100.0% |
| Damm | 90 | 90 | 0 | 100.0% |
| Weighted Mod 11 (2–7) | 90 | 90 | 0 | 100.0% |
| ISO 7064 MOD 11-2 | 90 | 90 | 0 | 100.0% |
| Simple digit sum mod 10 | 90 | 90 | 0 | 100.0% |
| Weights 2, 4 (even, mod 10) | 90 | 80 | 10 | 88.9% |
The last row uses even weights with modulus 10 to show how a poor weight choice misses substitutions.
What is Single-Digit Error Simulator?
A Single-Digit Error Simulator is a tool that measures how well a check digit algorithm detects 1 mistyped digit. Single-digit errors make up about 60–95% of human transcription errors in published studies.
Every standard scheme catches 100% of single substitutions. Weights that share a factor with the modulus (such as 2 with modulus 10) do not.
What are the uses of Single-Digit Error Simulator?
There are 3 main uses of the Single-Digit Error Simulator, including scheme design, algorithm teaching, and QA evidence.
- Scheme design: Engineers prove that a new weight pattern catches all substitutions.
- Algorithm teaching: Teachers show why weights must be coprime with the modulus.
- QA evidence: Testers document detection coverage for audits.