Graph Compression Calculator

Model graph compression using sparsity, communities, and entropy inputs. Compare storage across matrices and lists. Reveal savings, ratios, and efficiency for real network datasets.

Calculated Compression Results

This panel appears above the form so the latest submitted result is visible immediately.

Original Size 5.83 MB
Final Compressed Size 8.47 KB
Compression Ratio 704.9296:1
Space Savings 99.86%
Graph Density 0.002987
Compressed Nodes / Edges 1,560 / 3,268
Efficiency Index 91.87

Compression Stage Plot

Calculator Inputs

Total vertices in the original graph.
Unique stored connections before compression.
Used when the graph stores weighted edges.
Storage model for the original graph.
Storage model after graph compression.
Headers, dictionaries, offsets, and block indexes.
Models community merging or quotient graph reduction.
Represents removed, summarized, or merged edges.
Remaining percentage after repeated-pattern removal.
Remaining percentage after bit-level coding.
Estimated fidelity of the compressed representation.
Directed graphs allow ordered edge pairs.
Weighted graphs store extra value bits per edge.

Detailed Results Table

Metric Value
Original Representation Adjacency Matrix
Compressed Representation CSR Sparse Row
Directed Graph No
Weighted Graph Yes
Nodes 2400
Edges 8600
Theoretical Max Edges 2878800
Graph Density 0.002987
Average Degree 7.1667
Vertex Identifier Bits 12
Compressed Nodes 1560
Compressed Edges 3268
Original Size 5.83 MB (48,939,600.00 bits)
Structural Compressed Size 12.87 KB (105,407.00 bits)
After Deduplication 9.52 KB (78,001.18 bits)
After Entropy Coding 6.47 KB (53,040.80 bits)
Metadata Overhead 2,048 B
Final Compressed Size 8.47 KB (69,424.80 bits)
Compression Ratio 704.9296:1
Space Savings 99.86%
Absolute Savings 5.83 MB (48,870,175.20 bits)
Bits per Edge Before 5,690.6512
Bits per Edge After 21.2438
Quality Retention 92.00%
Compression Loss 8.00%
Efficiency Index 91.87

Interpretation Notes

Structure Impact

Structural compression reduced the graph to 1560 nodes and 3268 edges, which changes the base storage estimate before coding.

Savings Outlook

The current scenario yields 99.86% space savings with a quality retention estimate of 92.00%.

Practical Caution

Metadata, serialization rules, and storage alignment can raise final file size. Treat this tool as an engineering estimate rather than a byte-perfect filesystem measurement.

Example Data Table

Dataset Nodes Edges Output Format Original Size Compressed Size Ratio Savings
Road network 12,000 18,400 CSR Sparse Row 1.43 MB 412.87 KB 3.55:1 71.77%
Citation graph 5,500 23,900 Edge List 350.10 KB 153.80 KB 2.28:1 56.07%
Dense lab matrix 1,600 620,000 Adjacency Matrix 2.44 MB 1.08 MB 2.26:1 55.74%
Social cluster map 9,800 41,300 CSR Sparse Row 768.50 KB 229.44 KB 3.35:1 70.15%

Formula Used

1) Maximum Edges

Directed: maxEdges = n × (n − 1)

Undirected: maxEdges = n × (n − 1) / 2

2) Density and Average Degree

Density: density = edges / maxEdges

Average degree: directed uses edges / n, while undirected uses 2 × edges / n

3) Identifier Bit Width

vertexBits = ceil(log2(n))

4) Base Storage Estimate

Adjacency Matrix: cells × cellBits

Edge List: edges × (2 × vertexBits + weightBits)

CSR Sparse Row: (n + 1) × vertexBits + edges × (vertexBits + weightBits)

5) Structural Compression

compressedNodes = n × (1 − nodeReduction / 100)

compressedEdges = edges × (1 − edgeReduction / 100)

6) Bit-Level Compression

afterDedup = structuralBits × dedupFactor

afterEntropy = afterDedup × entropyFactor

finalCompressedBits = afterEntropy + metadataBits

7) Final Metrics

compressionRatio = originalBits / finalCompressedBits

savingsPercent = (1 − finalCompressedBits / originalBits) × 100

efficiencyIndex = savingsPercent × qualityRetention / 100

How to Use This Calculator

  1. Enter the original node and edge counts for your graph.
  2. Choose the original storage format and the target compressed format.
  3. Turn on directed or weighted mode when needed.
  4. Set bits per weight for weighted graphs.
  5. Enter node reduction and edge reduction percentages to model graph coarsening.
  6. Adjust deduplication and entropy retained-bit percentages to reflect coding strength.
  7. Add metadata overhead for dictionaries, offsets, block headers, or file indexes.
  8. Use quality retention to reflect how much structural fidelity remains after compression.
  9. Click Calculate Compression to update the results, chart, and export-ready table.

FAQs

What does this calculator measure?

It estimates how much storage a graph may need before and after compression. It combines structural reduction, deduplication, entropy coding, and metadata overhead into one final size estimate.

What is graph compression in this model?

Graph compression reduces nodes, edges, or repeated patterns while preserving useful structure. This page models coarsening, repeated-pattern removal, and bit-level encoding efficiency in a practical way.

Why do representation types matter?

An adjacency matrix, edge list, and CSR sparse row format store information differently. Sparse graphs often compress better when stored in list-based or CSR structures.

What does the entropy factor mean?

It represents the percentage of bits remaining after entropy coding. Lower values mean stronger coding efficiency, while higher values indicate less benefit from symbol compression.

Why can savings become negative?

Negative savings mean the compressed result is larger than the original estimate. That can happen when metadata is high, reduction rates are weak, or the chosen output structure is inefficient.

How should I choose node reduction?

Use it to model community aggregation, quotient graphs, or structural merging. Larger values mean more aggressive compression, but usually imply greater information loss in the original graph.

Is this suitable for weighted graphs?

Yes. Weighted graphs require extra bits per stored connection. The calculator includes a weight-bit input so size estimates can reflect costlier edge attributes.

Can I use this for exact production storage planning?

Use it for strong estimation, comparison, and scenario analysis. Real storage will also depend on file headers, serialization rules, hardware alignment, and implementation details.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.