Pearl is a fork of the Bitcoin protocol, so much of it will feel familiar — UTXOs, proof of work, a fixed supply cap, a script-based virtual machine. The differences are deliberate and mostly concentrated in four areas: what the mining work does, how coins are issued, which addresses are supported, and how difficulty adjusts.
Side by side
| Bitcoin | Pearl | |
|---|---|---|
| Mining work | SHA-256 hashing — no use beyond security | Matrix multiplication — powers AI inference and security |
| Total supply | 21 million BTC | 2.1 billion PRL |
| Issuance | Halves every ~4 years, in steps | Declines smoothly and continuously — no halvings |
| Block time | ~10 minutes | 194 seconds (3:14) |
| Difficulty adjustment | Every 2,016 blocks | Every block, via WTEMA |
| Address types | Legacy, P2SH, SegWit, Taproot | Taproot only |
| Post-quantum | Not built in | Groundwork in place (XMSS, P2MR) |
| Smallest unit | Satoshi (10⁻⁸ BTC) | Grain (10⁻⁸ PRL) |
| Mining hardware | ASICs | GPUs |
| Block header nonce | Yes | Removed — proofs are randomised, not nonce-searched |
OP_CAT | Disabled | Enabled |
The differences that matter most
1. The work is useful
The headline difference. Bitcoin's energy produces security and nothing else. Pearl's produces security and AI inference from the same GPU cycles. See What is Proof of Useful Work?
2. No halvings
Bitcoin's block reward drops by 50% overnight roughly every four years, creating revenue cliffs for miners and a thin long-term issuance tail. Pearl declines by a fraction of a percent per block instead — same fixed cap, no shocks. See Does Pearl have halvings?
3. Difficulty adjusts every block
Bitcoin recalculates difficulty every two weeks, which means a sudden change in hashrate leaves block times wrong for a long stretch. Pearl uses a weighted exponential moving average that updates each block, with a characteristic response time of about seven days. Block intervals stay closer to target when the network's compute changes quickly — which matters more for Pearl, since GPU capacity can move faster than ASIC capacity.
4. Taproot only
Pearl deliberately dropped support for legacy address formats — no P2PKH, no P2SH, no older SegWit variants. Every Pearl address is Taproot and begins with prl1p. Fewer formats means a smaller attack surface and less user confusion. See Understanding Pearl addresses.
5. Post-quantum groundwork
Pearl includes an opcode for XMSS, a hash-based signature scheme believed to resist quantum attack, plus the Pay-to-Merkle-Root output type from BIP-360, which minimises public key exposure. The XMSS opcode is currently disabled in consensus and reserved for future activation if Schnorr signatures are ever considered at risk. See Is Pearl post-quantum secure?
6. GPUs, not ASICs
Bitcoin mining is dominated by purpose-built ASICs. Pearl runs on the GPUs that already do AI work, and its resistance to specialised hardware is economic: an ASIC that could only mine Pearl would forfeit the useful-work revenue that makes Pearl mining worthwhile.
What's the same
- UTXO accounting. Coins live at addresses as discrete unspent outputs, not in account balances.
- Longest-chain consensus, measured by cumulative work.
- A fixed supply cap.
- First-price fee auction. Fees are the difference between a transaction's inputs and outputs, claimed by the miner.
- A stack-based, non-Turing-complete VM. Pearl is not a smart contract platform.
- Irreversible transactions. No one can reverse a confirmed transfer.
Pearl's node, wallet, and light client were originally forked from btcd, btcwallet, and neutrino — mature, well-reviewed Bitcoin implementations.
Read more
Technical specifications are in the Pearl whitepaper, Section 5.