What is a soft fork? How it changes a network
A soft fork is a backward-compatible rule change on a crypto network: old nodes still accept new blocks, while miners enforce the tighter rules.
Vahe HakobyanEditor-in-chief
Updated Oct 5, 20263 min readFact-checked
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It makes the rules stricter.
Why do soft forks happen?
Developers use a soft fork to add features or fix problems without forcing every node to upgrade. The change works with older software, so the network can adopt new rules gradually.
How does a soft fork work?
A soft fork makes the rules stricter. Updated nodes enforce the new rules and reject blocks that break them. Older nodes still accept the new blocks because those blocks also follow the old rules, but they cannot check the added rules.
How are soft forks activated?
Activation usually depends on miners. They signal support in the blocks they mine. Once enough miners signal within a period, the new rules lock in and then enforce.
- Miners signal support in blocks they mine.
- Support is counted over a set period.
- Once enough support is reached, the rules lock in.
- After lock-in, updated nodes enforce the rules.
What risks do soft forks have?
Soft forks can be contentious because they change how the network works, and they may fail if miners do not enforce the new rules.
Soft fork vs hard fork?
The main difference is compatibility. Old nodes accept soft fork blocks, but they reject blocks from a hard fork because those blocks break the old rules. A hard fork usually requires everyone to update to stay on the same network.
Frequently asked questions
It can, but this is less common. If miners disagree, a minority chain may appear and usually fades.
Usually no. Your coins stay on the same chain. You may need to update your wallet later to check the new rules.
Developers propose it, miners signal and enforce it, and node operators and users can accept or reject it by choosing their software.
It lets users and node operators signal support for a rule change by running software that enforces it, which can push miners to follow.
