Finance & Economics / Blockchain & Crypto
Bitcoin Transaction vBytes Calculator
UTXOs being spent
Destinations (recipient + change)
Bitcoin Transaction Sizes
What are vBytes?
Virtual Bytes (vBytes) is the unit used to measure transaction size for fee calculation. For SegWit transactions, vBytes account for the witness discount.
Typical Input Sizes:
- P2PKH (Legacy): ~148 bytes per input
- P2SH (SegWit wrapped): ~91 bytes per input
- Bech32 (Native SegWit): ~68 bytes per input
- Taproot: ~58 bytes per input
Typical Output Sizes:
- P2PKH: 34 bytes
- P2SH: 32 bytes
- Bech32: 31 bytes
- Taproot: 43 bytes
Fee Calculation:
Transaction Fee = vBytes × Fee Rate (sat/vB)
Example: 250 vBytes × 50 sat/vB = 12,500 sats
SegWit Savings:
SegWit (Bech32) and Taproot transactions are smaller due to witness data segregation, resulting in lower fees. Upgrading from legacy to SegWit can save 30-40% on fees.
💡 Tips for Lower Fees:
- Use SegWit (Bech32) or Taproot addresses
- Consolidate UTXOs when fees are low
- Batch multiple payments into one transaction
- Fewer inputs = smaller transaction size
- Use RBF (Replace-By-Fee) to adjust fees if stuck
Use this bitcoin transaction vbytes calculator to compute blockchain & crypto results from your inputs.