A comprehensive tool for calculating and visualizing Ethereum block sizes across different network configurations, including support for the Electra upgrade features.

Try it online: https://ethpandaops.github.io/blocksize/

The app runs entirely in your browser using stlite - no server required!

• Consensus Layer Calculations: BeaconBlock, attestations, slashings, exits, BLS changes
• Post-Electra Support: Deposit requests, withdrawal requests, consolidation requests
• Execution Layer Modeling: EIP-7623 effects, compression scenarios, gas limit variations
• Interactive Visualizations: Component breakdowns, size comparisons, parameter exploration
• Preset Configurations: Common network scenarios (mainnet, testnet configurations)
• Theoretical Worst-Case Analysis: Maximum possible block sizes under extreme conditions

# Clone the repository
git clone https://github.com/ethpandaops/blocksizes.git
cd blocksizes

# Install dependencies using uv (recommended)
uv sync

# Or using pip
pip install -r requirements.txt

# Run the Streamlit app locally
streamlit run app.py

# Or using the run script
./run.sh

The app will be available at http://localhost:8501

The app is automatically deployed to GitHub Pages using stlite. To update the deployment:

# Rebuild and deploy after making changes to app.py
./deploy.sh

Or manually:

# Just rebuild index.html from app.py
./build.sh

# Then commit and push
git add index.html
git commit -m "Update deployment"
git push

The calculator includes several preset network configurations and supports custom parameter adjustment for:

• Active validator counts (100k - 5M)
• Gas limits (15M - 1000M = 1 gigagas)
• All consensus layer operations with realistic limits
• EIP-7623 effects and compression scenarios

• BeaconBlock/Body: Fixed SSZ overhead (500 bytes)
• Attestations: EIP-7549 cross-committee aggregation support
• Slashings: Theoretical worst-case with maximum validator sets
• Post-Electra: New deposit system, withdrawal & consolidation requests

• EIP-7623: Calldata cost increases and size reductions
• Transaction Types: all_zeros, all_nonzeros, mixed, access_list scenarios
• Compression: Snappy compression effects on different data patterns
• Gas Conversion: Empirical gas-to-size conversion rates

• Runtime: stlite (Streamlit in browser via Pyodide)
• Hosting: GitHub Pages (static hosting)
• Build Process: Dynamic index.html generation from app.py
• Dependencies: Bundled client-side (numpy, pandas, plotly)

• ./build.sh - Rebuild index.html from app.py
• ./deploy.sh - Build and deploy to GitHub Pages
• ./run.sh - Run local Streamlit development server

1. Fork the repository
2. Create a feature branch
3. Make your changes to app.py
4. Test locally with streamlit run app.py
5. Run ./deploy.sh to update the live demo
6. Submit a pull request

This project is licensed under the MIT License - see the LICENSE file for details.