To create an altcoin in the full sense, you launch a native coin on a network of your own. An altcoin is any cryptocurrency other than Bitcoin. This guide compares the main routes, which are forking a codebase, building a chain with a framework, or launching a rollup. It also covers the settings you fix at genesis, the security risks, the cost and the launch steps.
Every route leaves you responsible for the security of a network. If an app only needs a tradable asset, a token on an existing chain is faster and cheaper and uses that chain's security. The cryptocurrency development guide compares coins and tokens; this page is for teams with a technical reason to run their own network.
Reasons for altcoin creation
Technical reasons for a new chain include a custom fee market, a special virtual machine, reserved block space for a high-volume app, privacy features that other chains lack, and control over upgrades. Marketing reasons, such as "a coin sounds more serious than a token" or "we want our own exchange listing", are weaker.
Exchanges, wallets and custodians must do integration work for each new chain, so a native coin is harder to list than a standard token on a known chain.
Ways to create an altcoin compared
| Route | Starting point | Where security comes from | Effort | Typical use |
|---|---|---|---|---|
| Fork Bitcoin or Litecoin | A C++ codebase with UTXO accounting and proof of work | Hashrate from your own miners | Low to start, high to maintain | Payment coins. Few new projects take this route today. |
| Fork a proof-of-stake client | An EVM-compatible or other proof-of-stake node | Coins staked by your validators | Medium | Teams that want EVM compatibility with their own validators |
| Cosmos SDK with CometBFT | A Go framework for app-specific chains with BFT consensus | Your validators, or a shared-security arrangement | Medium to high | App chains with custom modules that connect over IBC |
| Polkadot SDK (Substrate) | A Rust framework built from runtime modules called pallets | Your own validators, or Polkadot's shared security | High | Chains that want upgrades without hard forks and a link to Polkadot |
| Rollup frameworks (OP Stack, Arbitrum Orbit, ZK stacks) | A layer 2 or layer 3 chain that settles to Ethereum or another layer 2 | The settlement layer, plus the operator of your sequencer | Medium. Rollup-as-a-service vendors often run the setup. | EVM apps that need their own block space |
| Avalanche L1 (formerly called a subnet) | A custom chain built with Avalanche tools | Your own validator set | Medium | Permissioned or app-specific EVM chains |
A rollup can use your own coin as its gas token, which makes that coin the native coin of the rollup. Transaction ordering and data availability then depend on the stack you choose. The Polkadot development guide covers the Polkadot route in more detail.
Settings you decide at genesis
Consensus and security
A proof-of-work chain needs so much hashrate that an attacker would pay a lot to rent a majority of it. A new chain on a common algorithm such as SHA-256 or Scrypt competes with much larger networks, whose miners can switch their machines to your chain for a short time and attack it.
A proof-of-stake chain draws its security from the value of the staked coins. That value is small for a new coin, so a new network is fragile under either model.
Attackers have run such attacks on listed coins. Ethereum Classic suffered several 51% attacks in 2019 and 2020, and the attackers double-spent coins at exchanges. Bitcoin Gold was attacked in 2018 and again in 2020, and a brand-new fork has much less hashrate than those two coins had. The bitcoin mining software guide explains how hashrate costs work.
Monetary policy
- Supply schedule. Choose a fixed cap with halvings, a low permanent inflation rate, or new coins tied to the share of coins staked.
- Premine and allocations. Users and exchanges examine any coins created at genesis for founders or a treasury. Disclose these allocations and lock them in a vesting schedule.
- Block reward and fees. Decide who earns the reward and the fees, and whether the chain burns part of the fees.
Network settings
The team sets the block time, the block size or gas limit, and the address format and chain ID. A proof-of-work chain also needs a difficulty adjustment algorithm, and a proof-of-stake chain needs an unbonding period and slashing rules. A fork must change its chain ID and its address prefixes, because keeping its parent's allows replay attacks and confuses users.
Work after the code compiles
The team behind a new chain must provide these items after launch:
- Seed nodes, and validators or miners run by people outside the founding team.
- A block explorer and public RPC endpoints with rate limits.
- Wallet support. Ship a reference wallet, and add hardware wallet support for large holders. The crypto wallet development guide covers the options.
- Exchange integration notes. Document confirmation counts, node setup and memo handling, and keep a steady release schedule. Exchanges weigh the cost of running your node against the volume they expect. The crypto exchange listing guide covers what exchanges check.
- A security process. Accept bug reports, coordinate upgrades and ship emergency releases when needed.
- Upstream fixes. A fork of Bitcoin Core or another client must merge security fixes from the original project for as long as the chain runs, and many abandoned forks still run vulnerable code that is years old.
Interoperability and bridges
A new chain with no link to existing markets is isolated: users cannot bring stablecoins in, and your coin cannot reach the exchanges where people trade. Each route offers its own link:
- Cosmos SDK chains use IBC, a protocol that moves tokens and messages between chains using light clients.
- Polkadot SDK chains that connect to Polkadot use XCM messages.
- Rollups have a built-in bridge to their settlement layer, and a withdrawal from an optimistic rollup waits through a challenge period of about seven days, unless the user pays a third-party liquidity bridge.
Other chains rely on external bridges, which attackers have exploited many times. Harmony's Horizon bridge lost about $100 million in June 2022 after attackers took over keys of a small multisig wallet. If your chain depends on a bridge, the bridge's security model becomes part of your chain's security model. Tell users how the bridge is secured, for example by a multisig, a validator set, a light client or proofs.
Choosing a framework
| Question | What the answer points to |
|---|---|
| Do your developers and users rely on Ethereum tools? | A rollup or an EVM-based chain keeps the existing contracts and wallets. |
| Who will validate? | A proof-of-stake chain needs dozens of independent validators, while a rollup needs only one sequencer to start. |
| How much custom logic does the chain need? | Custom fee logic or native modules point to Cosmos SDK or Polkadot SDK, and standard smart contracts point to a rollup. |
| Which language does the team know? | Go for Cosmos SDK, Rust for Polkadot SDK, Solidity plus infrastructure skills for rollups, C++ for Bitcoin forks. |
| What happens if the chain gets little use? | Plan how apps can move to another chain without trapping users' assets. |
How to create an altcoin: launch steps
- Write a technical specification that explains why the project needs a new chain and which framework fits.
- Build a prototype on a local network, then run a public testnet for several months and invite outside validators or miners.
- Order security reviews of consensus changes, custom modules or pallets, bridges and the genesis file.
- Recruit independent validators or mining pools before mainnet, and document how to run a node.
- Launch mainnet with cautious settings. Some chains keep transfers disabled until the validator set is stable.
- Add integrations with explorers, wallets, bridges and exchanges, and publish developer documentation.
Cost and timeline estimates
A developer can compile a fork of a proof-of-work codebase with only cosmetic changes in days, and thousands of such forks exist, most of which no longer run.
A serious chain costs far more. The figures below are estimates based on typical team sizes, not quotes:
- A Cosmos SDK or Substrate chain with a few custom modules needs four to eight engineers for six to twelve months before mainnet, covering protocol code, Go or Rust, DevOps and front end, and a permanent core team after launch.
- Rollup-as-a-service vendors can start a layer 2 in weeks for a monthly fee, but sequencer operations, bridges and ecosystem work remain the project's job.
- Audits of consensus code cost more than token audits and take longer to schedule.
Legal points
A sale of coins before or at launch can count as a securities offering in the US and in other countries. In the EU, MiCA requires a white paper for most public offers of crypto-assets and for admission to trading. A coin that is distributed only through mining or staking faces fewer of these legal questions, though not none, and regulators look closely at premines and team allocations.
Frequently asked questions
What is the easiest way to create an altcoin?
The easiest technical route is to fork a Bitcoin-based codebase and change its settings, but that route is also the most likely to produce an insecure chain that nobody maintains. A rollup or a framework-based chain takes more work and has a better chance of lasting.
Can I make my own coin without coding?
Token generators deploy a token without code, but the result is a token on another chain, not a coin. Running your own chain needs engineering and operations skills for as long as the chain runs.
Should a new coin use proof of work or proof of stake?
For a new network, proof of stake or the security of a rollup's settlement layer is usually safer. An attacker can rent enough hashrate to attack a small proof-of-work coin. Proof of work suits a project that wants a specific mining community and accepts that risk.
How does an altcoin get listed on exchanges?
Exchanges check security, liquidity, legal status and the cost of integration. Clear node documentation, a record of stable releases and real usage help, but paying a middleman who promises a listing does not.
What is a premine?
A premine is the set of coins created at genesis instead of earned through mining or staking. A large premine that was not disclosed is a warning sign to users and exchanges. Disclosed allocations with vesting are standard.
Does a game or app need its own blockchain?
Usually not, because separate block space helps only at high transaction volumes. Most apps launch on an existing layer 1 or layer 2 and move to an app chain or rollup if usage grows enough.