Fees and Transaction Sizes
Tidecoin transactions are larger than comparable Bitcoin transactions because post-quantum public keys and signatures are larger than ECDSA or Schnorr data. Fees still follow the Bitcoin-like idea of paying by virtual size.
This page explains the concept for users. Integration details live in Transaction Size and Fees.
Why Transactions Are Larger
A Falcon-512 padded signature is 666 bytes before the sighash byte. A serialized Falcon-512 public key is 898 bytes including Tidecoin’s scheme prefix. That makes a typical Tidecoin spend much larger than a comparable Bitcoin ECDSA spend.
Other post-AuxPoW schemes are larger:
| Scheme | Public key bytes | Signature bytes |
|---|---|---|
| Falcon-512 | 898 | 667 with sighash |
| Falcon-1024 | 1,794 | 1,281 padded with sighash |
| ML-DSA-44 | 1,313 | 2,421 with sighash |
| ML-DSA-65 | 1,953 | 3,310 with sighash |
| ML-DSA-87 | 2,593 | 4,628 with sighash |
Only Falcon-512 is mainnet-active before AuxPoW.
How Fees Are Calculated
Tidecoin uses the standard weight and virtual-size model:
weight = stripped_size * 4 + witness_size
vbytes = ceil(weight / 4)
fee = vbytes * fee_rateWallets normally handle this automatically. If you build transactions yourself, estimate fees from the final signed transaction, not from a Bitcoin template.
Worked Example
A rough one-input, two-output Falcon-512 witness-v0 transaction can be around:
| Component | Approximate virtual size |
|---|---|
| Base overhead | 12 vB |
| One Falcon-512 input | 434 vB |
| Two witness-v0 outputs | 62 vB |
| Total | 508 vB |
At 2 atoms/vB, the fee would be about 1,016 atoms. At 10 atoms/vB, it
would be about 5,080 atoms.
Treat this as an explanation, not a broadcast rule. The final fee should come from the signed transaction and your node’s current fee policy.
Why This Is Acceptable
Post-quantum signatures buy a different security property than ECDSA. The cost is larger transaction data. Tidecoin’s design accepts that cost and keeps the rest of the transaction and fee model familiar.
Block space still matters. Exchanges, pools, wallets, and high-volume services
should batch where appropriate, use the wallet’s fee estimator, and test custom
transactions with testmempoolaccept.
User Rules
- Let the wallet choose fees unless you have a specific reason not to.
- Do not compare Tidecoin transaction size directly to Bitcoin ECDSA size.
- Use a small test transaction when trying a new wallet or destination.
- For stuck transactions, check the wallet, mempool policy, and node logs before assuming the network is broken.
See also: Transaction Size and Fees, Protocol / Transactions, Signature Schemes Explained.