Cycle trackerHalvingsBull · Dip
Halving clock and the four-year cycle
Price on 8 Oct 2026: ~$82,600All-time high: $126,198 · 6 Oct 2025~35% below the high
Next halving · live~Apr 2028loading live block height…
1,050,000halving block
What to watchOct – Nov 2026Pattern bottom window. Past bears bottomed 364–406 days after the peak, which puts this one between about 5 Oct and 16 Nov 2026.
~Apr 2028Fifth halving at block 1,050,000. Block reward drops from 3.125 to 1.5625 BTC.
~Sep – Oct 2029Pattern peak window. The last three peaks came 525–547 days after their halving.
$200,000Needs about 1.6× the $126k high. Each peak has beaten the last by less: about 17×, then 3.5×, then 1.8×. If that keeps shrinking, $200k lands at the very top of the 2029 peak, or not at all this cycle.
Past cycles| Halving | Peak | Days to peak | Peak price | Bear bottom | Drawdown |
|---|
| 28 Nov 2012 | Dec 2013 | ~371 | ~$1,150 | Jan 2015 · ~$150 | −87% |
| 9 Jul 2016 | 17 Dec 2017 | ~525 | ~$19,700 | Dec 2018 · $3,122 | −84% |
| 11 May 2020 | 10 Nov 2021 | ~547 | ~$69,000 | Nov 2022 · $15,476 | −78% |
| 20 Apr 2024 | 6 Oct 2025 | ~534 | $126,198 | Low so far: 5 Jun 2026 · ~$59,100 | −53% so far |
Pattern, not a promiseFour cycles is a small sample, and the 2024 cycle already broke the mold: Bitcoin set a new high before its halving, thanks to the spot ETFs. The dates above are where the old pattern points, not a forecast. Not financial advice.
Sites that track the cycle WhitepaperProtocolPrimary source
Bitcoin: A Peer-to-Peer Electronic Cash System
Satoshi Nakamotobitcoin.org31 Oct 20089 pages · 12 sections · 8 references
The problem it solvesOnline payments depend on banks and processors acting as trusted third parties. That makes payments reversible, which pushes up costs, kills small transactions, and forces merchants to collect more information and accept some fraud. Digital signatures can prove who owns a coin, but without a central mint nobody can stop the same coin being spent twice.
The proposal: a peer-to-peer network that timestamps transactions into a chain of hash-based proof-of-work. The chain with the most work behind it is both the record of what happened and proof that the largest pool of CPU power agreed to it. The system stays secure as long as honest nodes control more CPU power than any group of cooperating attackers.
Core mechanicsCoinA chain of digital signatures. Each owner signs a hash of the previous transaction plus the next owner's public key.
Timestamp chainEach block's hash includes the previous block's hash, so every new block reinforces the ones before it.
Proof-of-workHashcash-style. Increment a nonce until the SHA-256 block hash starts with enough zero bits. One CPU, one vote.
Longest chainNodes treat the chain with the most work as correct. Ties resolve when the next block lands.
IncentiveThe first transaction in each block mints new coins for its creator, later replaced by transaction fees.
Merkle treeTransactions hash into a single root, so spent history can be pruned without breaking the block hash.
Section by section§1 · IntroductionTrust-based payments are reversible and costly. What's needed is payment based on cryptographic proof.
§2 · TransactionsCoins as signature chains. Preventing double-spends without a mint requires a public, agreed transaction order.
§3 · Timestamp serverHash a block of items, publish the hash, and chain each timestamp to the last.
§4 · Proof-of-workWork makes blocks costly to change. Difficulty adjusts to keep a target block rate.
§5 · NetworkThe six steps nodes follow, from broadcasting transactions to building on the accepted block.
§6 · IncentiveBlock rewards distribute coins and make playing by the rules pay better than attacking.
§7 · Reclaiming disk spaceMerkle pruning. Headers alone run about 4.2 MB a year.
§8 · Simplified payment verificationLight clients keep only headers and check a transaction's Merkle branch.
§9 · Combining and splitting valueMultiple inputs and outputs, usually one payment output and one change output.
§10 · PrivacyTransactions are public but keys are anonymous, like a stock tape. Use a new key pair for each transaction.
§11 · CalculationsAn attacker catching up is a Gambler's Ruin problem. The odds fall exponentially with each confirmation.
§12 · ConclusionNodes vote with CPU power. Rules and incentives are enforced by that consensus.
Numbers in the paper10 minassumed block interval
80 Bblock header, no transactions
4.2 MBheaders per year
6steps to run the network
How many confirmations? (§11)Confirmations (z) a recipient should wait for an attacker's chance of rewriting the payment to fall below 0.1%, by the attacker's share of network hash power (q). Results from the paper's own C code.
| Attacker hash share (q) | Confirmations needed (z) |
|---|
| 10% | 5 |
| 15% | 8 |
| 20% | 11 |
| 25% | 15 |
| 30% | 24 |
| 35% | 41 |
| 40% | 89 |
| 45% | 340 |
Attacker with 10% of hash powerSuccess chance drops from 20.5% at 1 confirmation to 0.09% at 5 and about 0.0001% at 10.
Attacker with 30% of hash powerStill 17.7% at 5 confirmations and 4.2% at 10. It takes about 24 to get under 0.1%.
Reading notesThe paper never uses the word “blockchain”; it says “chain of blocks.” The 10-minute interval and the moving-average difficulty target are stated as assumptions here, and the fixed 21 million supply and halving schedule are not in the paper at all; they came with the software released in January 2009. The SPV alert idea in §8 was never built as described. The 2008 storage estimate assumed 2 GB of RAM in a typical computer.
What it builds on · references- W. Dai, "b-money," 1998
- H. Massias, X.S. Avila, J.-J. Quisquater, secure timestamping with minimal trust, 1999
- S. Haber, W.S. Stornetta, "How to time-stamp a digital document," J. Cryptology, 1991
- D. Bayer, S. Haber, W.S. Stornetta, improving digital time-stamping, 1993
- S. Haber, W.S. Stornetta, "Secure names for bit-strings," ACM CCS, 1997
- A. Back, "Hashcash: a denial of service counter-measure," 2002
- R.C. Merkle, "Protocols for public key cryptosystems," IEEE S&P, 1980
- W. Feller, An Introduction to Probability Theory and Its Applications, 1957
Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. 2008. https://bitcoin.org/bitcoin.pdf. Summary and figures taken from the PDF at that address.