Bitcoin Cash (BCH) Explained

Bitcoin Cash (BCH) is the SHA-256 proof-of-work chain that split from Bitcoin on August 1, 2017, at block 478,558, over one question: should Bitcoin scale by raising the block size? BCH answered yes — today running 32MB blocks with sub-cent fees — while keeping Bitcoin’s 21-million supply, its 210,000-block halvings, and a coinbase that pays the block finder everything. For solo miners it occupies a unique position: the first rung below Bitcoin on the difficulty ladder, and the only rung that combines reachable odds with deep, liquid markets.

Key takeaways

• Same money, different bet on scale. BCH shares Bitcoin’s supply cap, emission schedule, halvings, and pre-2017 ledger history. What forked was the philosophy: BCH scales on-chain (8MB at birth, 32MB today, an adaptive limit since 2024) to keep fees below a cent and function as spendable cash.
• The miner keeps 100% of the coinbase. Unlike its own descendant eCash (58% to the miner), BCH routes the entire block reward — currently 3.125 BCH plus fees — to whoever finds the block. On the SHA-256 ladder, that makes BCH the largest whole prize outside Bitcoin itself.
• ASERT retunes difficulty every block. Since November 2020, BCH difficulty adjusts continuously with a two-day half-life — no 2,016-block retarget cliff, no free windows for hit-and-run hashrate. Your odds today reflect the network as it is today.
• Live odds (July 2026, difficulty ~504 billion — 1/265th of Bitcoin’s): an S21-class ASIC expects a BCH block in about 107 days; an S23 in ~79; a single Bitaxe turns it into a ~69-year lottery — long, but 265× shorter than the same device on BTC.
• The chain evolves on a fixed calendar. Upgrades activate every May 15: CashTokens (2023), the adaptive block-size algorithm (2024), VM limits and big integers (2025), and the 2026 “Layla” upgrade bringing loops, functions, and richer contracts — a cadence that keeps the chain moving without surprise forks.

This is chapter two of our Know Your Chain series — after eCash (XEC), the profile of the chain that sits one honest step below Bitcoin. If XEC is the ladder’s technically adventurous middle, BCH is its conservative first step down: familiar rules, familiar economics, dramatically different odds.

The origin story: Bitcoin’s civil war

From 2015 to 2017, Bitcoin fought itself over a single constant: the 1MB block-size limit. As adoption grew, blocks filled, fees spiked, and confirmations slowed. One camp held that the limit protected decentralization and that scale belonged on second layers; the other held that Satoshi’s peer-to-peer electronic cash had to stay cheap enough to actually spend, and that meant bigger blocks. Years of proposals, conferences, and failed compromises couldn’t close the gap — so on August 1, 2017, at block 478,558, the big-block camp forked away. Bitcoin Cash launched with 8MB blocks and a claim to the original whitepaper’s vision.

The family tree kept branching. In November 2018 a dispute over protocol direction split off Bitcoin SV in the infamous “hash war”. In November 2020, a fight over funding development from the coinbase split off Bitcoin Cash ABC — which became eCash. Each split left BCH more defined: on-chain scaling, no protocol-level developer tax, upgrades by community consensus on a fixed schedule. Whatever you think of the forks, the miner-relevant result is a chain with a very clear identity and a very clean coinbase.

Why the block height beats Bitcoin’s

Here’s the detail that wins bar bets: BCH and BTC share every block up to 478,558 — yet today BCH’s chain is roughly 1,500 blocks ahead (≈958,000 vs ≈956,500 in July 2026). Same genesis, same 10-minute target… how?

The answer is 2017’s Emergency Difficulty Adjustment. Newborn BCH had a tiny fraction of SHA-256 hashrate, and with Bitcoin’s slow 2,016-block retarget it risked freezing solid. The EDA slashed difficulty whenever blocks came too slowly — which worked, but overcorrected: miners learned to pile in at low difficulty, mint fast blocks, and leave, sending the chain through wild oscillations that at times produced blocks in minutes. Those frantic months minted thousands of extra blocks — a permanent head start (and, since supply is height-based, an acceleration of BCH’s halving clock: BCH halved in April 2024 a couple of weeks before Bitcoin, and will keep leading by a similar margin in 2028). The EDA was replaced within months, and its lesson eventually produced one of BCH’s best features.

ASERT: the difficulty algorithm built for a minority chain

That feature is ASERT (aserti3-2d), live since November 2020. Instead of recalculating difficulty every 2,016 blocks like Bitcoin, ASERT retunes it every block, exponentially steering the chain back to its 10-minute schedule with a two-day half-life: if blocks run fast, difficulty rises smoothly and immediately; if hashrate leaves, difficulty decays just as smoothly, with no cliff and no waiting.

For a solo miner this matters in two directions. It removes the exploit: on old-style retarget chains, opportunistic hashrate can raid the easy window after a difficulty drop and vanish before the correction — the dynamic our BC2 retarget guide explores on a chain where windows still exist. On BCH there is no window to raid, which protects the steady miner’s share of the lottery. And it keeps the chain honest in real time: the difficulty you see is a live price, not a two-week-old average. The trade-off is symmetrical — you can’t time a BCH difficulty drop, because everyone’s odds move together, continuously.

Tokenomics: Bitcoin’s economics, unedited

Two rows carry the miner’s story. The 100% coinbase makes BCH the reference point of the series: when we profiled XEC’s 58% miner share, this is the baseline it was measured against. And the fees row deserves honesty in both directions: sub-cent fees are the chain’s whole identity as cash, which means fee income adds almost nothing to a block today — you are mining for the subsidy — while the long game (CashTokens activity, the 2026 contract upgrades) is precisely an attempt to grow blockspace demand without breaking the sub-cent promise.

The modern chain: what BCH became after the wars

The forks ended years ago; what remains is a chain shipping on a metronome. Every May 15 an upgrade activates: CashTokens (2023) brought native fungible tokens and NFTs to the UTXO model; the adaptive block-size limit (2024) let capacity grow algorithmically with demand; VM limits and big-integer arithmetic (2025) expanded what contracts can compute; and the May 15, 2026 “Layla” upgrade activated four CHIPs including loops and functions — pushing BCH from “payments plus tokens” toward genuinely programmable cash, with DEXes, escrow, and stablecoin rails built in CashScript on proof-of-work foundations. Add CashFusion for optional privacy and double-spend proofs for fast-payment safety, and the 2026 chain is less a Bitcoin nostalgia project than a parallel experiment with its own trajectory. For miners, the upgrade cadence is itself the signal: development is alive, scheduled, and consensus-driven — no surprise forks since 2020.

Mining economics: what your hardware expects (live numbers)

At the live network state (July 2026: difficulty ~504 billion, network hashrate ~4.1 EH/s — 1/265th of Bitcoin’s difficulty):

The strategic reading: BCH is where solo mining becomes plausible for a single modern ASIC while the prize remains instantly liquid. One S21-class machine expects a block a few times a year — enormous variance applies, as always governed by the Poisson math — and 3.125 BCH sells on every major exchange on Earth within minutes of maturity. Smaller chains offer shorter odds on thinner prizes; Bitcoin offers the grand prize at 265× the distance. BCH is the ladder’s liquidity-weighted sweet spot, which is exactly why it’s most miners’ first step down. Run your own hashrate through the calculator to see where you land.

The honest risks

Security budget and hashrate rotation. BCH runs on a small fraction of the SHA-256 ocean — roughly 0.4% of Bitcoin’s hashrate at today’s snapshot — and hashrate rotates with profitability, which is why exchanges customarily wait ~10 confirmations. Deep-reorg attacks have remained theoretical for years, and ASERT plus double-spend proofs blunt the classic vectors, but a minority chain’s security is a budget, not a birthright. Miner-profitability stress: 2026 analyses put BCH mining profitability below equilibrium — mining BCH solo is a lottery position, not an income strategy, exactly like every chain in this series. Price volatility and identity: BCH remains far more volatile than BTC, brand confusion with Bitcoin still costs adoption, and its cash thesis competes with both Bitcoin’s layer-2 story and fast alt-L1s. The counterweight is what the risks buy you: the only sub-Bitcoin SHA-256 chain where a solo win converts to a deep, liquid, decade-old market the same afternoon.

How to actually mine it

Get a BCH wallet and CashAddr address (it starts with bitcoincash:). Point any SHA-256 hardware — or rented hashrate — at a BCH solo endpoint with that address as the username. When a share clears ~504 billion difficulty, the coinbase pays you 3.125 BCH directly, and after 100 confirmations (~17 hours) it spends anywhere. Step-by-step configuration lives in the setup wizard, and the deeper walkthrough in our BCH solo mining tutorial.

Conclusion

Bitcoin Cash is what happens when Bitcoin’s original economics keep running under a different scaling philosophy: the same 21 million coins, the same halvings, an unedited 100% coinbase — wrapped around 32MB blocks, sub-cent fees, per-block difficulty, and a yearly upgrade metronome that in 2026 made the chain properly programmable. For solo miners it is the ladder’s pivotal rung: the first place your ASIC’s odds become believable, and the last place the prize stays perfectly liquid.

Know the chain — its war stories, its ASERT armor, its honest security budget — and the decision, as ever, reduces to arithmetic you can check. Chapter three of Know Your Chain will climb the rest of the ladder.