What is Fractal Bitcoin?
Fractal Bitcoin is a separate proof-of-work blockchain that runs a modified copy of Bitcoin Core, the software behind Bitcoin, with a block about every 30 seconds instead of every 10 minutes. Because it keeps Bitcoin's address formats and script rules, wallets and tools built for Bitcoin, and Bitcoin token standards such as BRC-20, Ordinals and Runes, work on it with few changes. Its mainnet went live on 9 September 2024, built by core contributors from UniSat, a Bitcoin Ordinals wallet and marketplace.
FB is Fractal's native token. It pays the fees for every transaction on the network and rewards the miners and indexers who produce its blocks. FB is not bitcoin: it is a different coin on a different chain, and there is no built-in way to move BTC onto Fractal and back.
Fractal Bitcoin at a glance
| Item | Detail |
|---|---|
| Type | Proof-of-work blockchain built from Bitcoin Core code |
| Native token | FB |
| Mainnet launch | 9 September 2024 |
| Block time | About 30 seconds |
| Mining algorithm | SHA-256d, the same as Bitcoin, so Bitcoin mining machines work on it |
| Consensus | Cadence Mining: merged mining, permissionless mining and index mining |
| Maximum supply | 210 million FB |
| Block reward | 6.25 FB since the first halving on 8 September 2026 (was 25 FB) |
| Token standards | BRC-20, Ordinals and Runes |
| Peg to Bitcoin | None; FB and BTC are separate assets |
How does Fractal Bitcoin work?
Fractal takes Bitcoin Core, packages it as a software instance with its own block production, and runs it as an independent network. The name comes from mathematics: a fractal is a pattern that repeats at every scale, and the project describes its network as "fractals of Bitcoin". The design allows further instances to be stacked on top of each other in future, each inheriting the structure of the one below. As of October 2026, the live network is a single layer, and the recursive multi-layer version remains a plan.
Fractal is also not a hard fork of Bitcoin in the way Bitcoin Cash is. A hard fork splits an existing chain and keeps its history and balances. Fractal reuses Bitcoin's 2009 genesis block as its starting point, but its own chain began on 9 September 2024, so no one's bitcoin balance carried over and every FB has been created since then.
Faster blocks mean faster confirmations and lower fees per transaction, which is why Fractal appeals to people who inscribe and trade Ordinals and BRC-20 tokens. The trade-off is that Fractal's security comes from its own miners, not from Bitcoin itself.
Cadence Mining: how Fractal is secured
Fractal splits block production between different kinds of participants, a design it calls Cadence Mining.
Merged mining: Bitcoin miners can secure Fractal with the same proof of work they already do for Bitcoin, at almost no extra cost, and earn FB on top. Mining pools that together control most of Bitcoin's hashrate support merged mining Fractal.
Permissionless mining: miners point SHA-256d hashpower at Fractal alone and compete directly for its blocks.
Index mining: added by the FIP-101 upgrade, which went live at block 1,764,000 on 14 May 2026. Indexers keep the data layer that BRC-20 balances and inscriptions depend on, and FB holders can stake to an indexer, without a lock-up, to share its rewards. Their FB stays in their own address while staked.
Until FIP-101, one block in three was merge-mined and two were mined permissionlessly. Since FIP-101, each of the three methods gets one block in every three-block cycle.
The FB token and its supply
FB pays transaction fees on Fractal, rewards miners and indexers, is staked in index mining, and is used to vote on proposals through Fractal Vote. Its maximum supply is 210 million FB, ten times Bitcoin's 21 million. The live circulating supply is shown in the market data on this page.
| Allocation | Share of 210 million FB | Terms |
|---|---|---|
| Mining rewards | 50% (105 million) | Paid to miners and indexers block by block, with halvings |
| Ecosystem treasury | 15% | At most 10% of the pool released per year, over 10 years |
| Core contributors | 15% | Locked for 7 months, then released by month 12 |
| Community grants | 10% | Funding for builders on Fractal |
| Advisors | 5% | At most 20% of the pool released per year, over 5 years |
| Pre-sale | 5% | Locked for 7 months, then released by month 12 |
Half of the supply was set aside before mining began, and that was the most criticized part of the launch. Critics pointed out that insiders held a share that would take miners years to earn. Fractal's answer is that the treasury is locked on chain with Bitcoin's time-lock opcode and that its addresses are public. The contributor and pre-sale allocations finished unlocking about a year after launch, in 2025.
The first halving and FIP-102
Like Bitcoin, Fractal cuts its block reward on a fixed block schedule, every 2,100,000 blocks, which at 30-second blocks is roughly every two years. The first halving happened at block 2,100,000 on 8 September 2026.
It went further than a normal halving. Under the FIP-102 upgrade, the reward fell from 25 FB to 12.5 FB as scheduled, and the second halving was brought forward at the same time, so blocks on Fractal now pay 6.25 FB. The other 6.25 FB per block becomes a budget for distributing FB to users for activity on the Bitcoin main chain. The rules for that are left to a later proposal, FIP-103, with testing planned from late 2026 and a full rollout targeted for the first quarter of 2027. The maximum supply stays at 210 million FB, and the 1:1:1 split between the three mining methods is unchanged.
What can you do on Fractal Bitcoin?
BRC-20 tokens: Fractal supports the BRC-20 token standard natively and adds a single-step transfer, simpler than the two-step transfer used on Bitcoin.
Ordinals and inscriptions: you can inscribe and trade Ordinals-style digital artifacts on Fractal, usually for much lower fees than on Bitcoin.
Runes: the Runes token protocol from Bitcoin also works on Fractal.
OP_CAT and smart contracts: Fractal switched on OP_CAT, an opcode that Satoshi Nakamoto disabled on Bitcoin in 2010. It lets developers build covenants and more expressive smart-contract logic than Bitcoin currently allows.
Decentralized exchanges: several DEXs for BRC-20 assets run on Fractal.
BRC-20 tokens can be bridged between Bitcoin and Fractal through whitelisted apps rather than a protocol-level bridge.
Is Fractal Bitcoin a sidechain or a layer 2?
By the usual definitions, no. A sidechain such as Liquid or Rootstock has a two-way peg: you lock BTC on Bitcoin and receive an equal amount on the sidechain, which you can later redeem. Fractal has no peg, so BTC cannot move onto it one for one. A layer 2 such as the Lightning Network settles back to Bitcoin itself, which Fractal does not do either.
Fractal launched using "Bitcoin layer" language, and a 2024 technical review in Bitcoin Magazine called that misleading for a chain with no peg. The review also argued that permissionless mining gives miners a reason to divert hashpower from Bitcoin as FB becomes more valuable. Fractal has since changed its own wording: its FAQ describes the network as a system of recursive Bitcoin Core instances, "not a traditional sidechain or L2".
Fractal Bitcoin vs other Bitcoin scaling projects
| Project | Approach | Link to Bitcoin | Native token |
|---|---|---|---|
| Fractal Bitcoin | Separate chain running Bitcoin Core code, 30-second blocks | Merged mining for one block in three; no peg | FB |
| Lightning Network | Payment channels for instant payments | Channels open and close on Bitcoin; uses real BTC | None (BTC) |
| Liquid | Federated sidechain | Two-way peg to BTC run by a federation | L-BTC (pegged BTC) |
| Rootstock | Smart-contract sidechain | Merged mining for every block plus a two-way peg | RBTC (pegged BTC) |
| Stacks | Smart-contract layer | Anchored to Bitcoin; sBTC as pegged BTC | STX |
The key column is the link to Bitcoin. The others either use real BTC or a pegged version of it. Fractal does neither: it borrows Bitcoin's code and part of its mining power, but runs its own coin.
Who created Fractal Bitcoin?
Fractal was built by core contributors from UniSat, a Bitcoin wallet and marketplace for Ordinals and BRC-20 tokens, together with Block Space Force, a development and investment firm. Changes to the protocol are made through numbered Fractal Improvement Proposals (FIPs), such as FIP-101 for index mining and FIP-102 for the 2026 halving. The code is open source.
Risks to know
FB's price can move sharply in either direction, and it has fallen a long way from its first days of trading. Half of the supply went to insiders and funds rather than to miners, and the treasury still releases tokens each year. Fractal has no peg to Bitcoin and is secured by less mining power than Bitcoin itself, its new reward rules (index mining and the Bitcoin mainnet budget) are recent or still being designed, and BRC-20 and inscription apps depend on indexers working correctly. Because Fractal uses the same address formats as Bitcoin, a Fractal address looks exactly like a Bitcoin address, so always check which network a wallet or service is sending on. This page explains how Fractal Bitcoin works and is not financial advice.
Fractal Bitcoin and Bitcoin.com
The Bitcoin.com Wallet does not list Fractal among its supported networks, so FB can't be held or swapped there today. If you want bitcoin itself, you can buy BTC with a card or bank transfer and hold it in the self-custody Bitcoin.com Wallet, where you keep your own keys. Never send BTC to a Fractal address or FB to a Bitcoin wallet that does not support Fractal.
