Shannon Diversity Index Calculator
Quantify biodiversity using Shannon entropy. Enter species counts to evaluate diversity, evenness, and dominant species for ecological surveys, classrooms, or field reports.
Total individuals
90
Shannon index (H')
1.473
Evenness (J')
0.915
Dominant species count
30
How to Use This Calculator
Collect species counts
Record the number of individuals observed for each species in the sample area.
Enter data and add species if needed
Use the provided fields to input species abundances. Add or remove species rows to match your dataset.
Review diversity metrics
Shannon index summarizes diversity, while evenness shows how balanced abundances are across species.
Formula
H' = −Σ pi ln pi
J' = H' / ln(S)
Example: Species counts [30, 25, 18, 12, 5] yield H' ≈ 1.54 and evenness 0.96, indicating a fairly balanced community.
Higher H' values reflect greater diversity; evenness ranges from 0 to 1.
About the Shannon Diversity Index Calculator
Shannon entropy integrates both species richness and abundance distribution, making it a popular metric in ecology, microbiome studies, and conservation planning.
When to Use This Calculator
- Biodiversity surveys: Summarize vegetation or wildlife plot data.
- Microbial ecology: Compare community diversity across samples.
- Environmental monitoring: Track ecosystem changes over time or before/after interventions.
- Education: Demonstrate diversity concepts in biology classrooms.
Why Use Our Calculator?
- ✅ Flexible input: Add as many species as needed.
- ✅ Immediate insights: Provides Shannon index, evenness, and dominance.
- ✅ User-friendly: Suitable for field teams without specialized software.
- ✅ Shareable: Summaries ready for reports and presentations.
Common Applications
Conservation planning: Identify habitats with high biodiversity value.
Urban ecology: Evaluate green space diversity in cities.
Restoration projects: Measure success by tracking diversity over time.
Tips for Best Results
- Ensure consistent sampling effort across sites for valid comparisons.
- Combine with richness and Simpson indices to capture different diversity dimensions.
- Use log base 2 for bits or base 10 for Hartleys if needed; this calculator uses natural log.
- Filter out rare species carefully; excluding them can underestimate diversity.
Frequently Asked Questions
Can I enter relative abundances instead of counts?
Yes. As long as values sum to 1 (or any constant), the index remains accurate. Counts are easier for most surveys.
How sensitive is H' to sample size?
Small sample sizes can underrepresent rare species. Increase sampling effort for more reliable estimates.
What if evenness returns N/A?
Evenness requires at least two species with non-zero counts. Add more species or revisit sampling methods.
How do I export results?
Copy the outputs directly or integrate the logic into data sheets; future updates will include downloadable reports.