--- title: Immutability url: "https://www.unknowngravity.com/en/glosario/inmutabilidad" site: Unknown Gravity published: "2025-06-07T15:22:23+00:00" modified: "2026-07-15T10:51:28+00:00" language: en-US description: "La immutability It's a fundamental property of blockchain technology which guarantees that the information recorded in a block cannot be modified or deleted once it has been validated and added to…" section: "Home > Immutability" --- # Immutability GLOSSARY · BLOCKCHAIN & WEB3 Immutability means a validated block cannot be rewritten: hash chaining plus PoW or PoS consensus enforce it. See how it holds and where it actually matters. WHAT IS IT? · FOR DUMMIES In blockchain, **immutability** means that **once something is written, it cannot be deleted or changed**. If you make a transaction, that information is recorded forever. This helps everyone trust that the data hasn't been manipulated and that the history is transparent. WHAT IS IT? · PRO **Immutability** is a **fundamental property of blockchain technology** that guarantees that the information recorded in a block **cannot be modified or deleted** once it has been validated and added to the chain. This is achieved through the use of **cryptographic hash functions**, chained block structures and decentralized consensus mechanisms (such as PoW or PoS), which prevent the rewriting of history without altering the entire network. Each block contains a unique hash generated from your data and the hash of the previous block. This creates a **cryptographically linked chain**, where any change in a block would alter its hash, breaking continuity and alerting the entire network. In addition, nodes that participate in decentralized validation ensure that only new blocks are accepted if they are valid according to the rules of consensus. Immutability is key in **environments where trust, traceability and data integrity are critical**, as in the **Tokenization of assets**, **financial systems**, **digital identity**, **supply chain**, **electronic voting** or **information auditing**. It ensures that the transaction history is verifiable, transparent and resistant to internal or external manipulation. Although it is technically possible to modify a blockchain through a 51% attack or a consensual hard fork, practical immutability depends on **decentralization, cryptographic security and protocol governance**, making it a strong guarantee of integrity for most business and legal use cases. ## 01 / Key points - It is the property that prevents modifying data already registered in the blockchain - It is based on cryptographic hashes, distributed consensus and block structure - It ensures that the history is **complete, verifiable and resistant to manipulation** - Key to traceability, trust and regulatory compliance - Applies to transactions, smart contracts, tokens and digital records ## 02 / Advantages - **Guaranteed integrity**: no one can alter the past without being detected - **Full transparency**: everyone can audit the blockchain - **Trust without intermediaries**: the network protects the veracity of the information - **Strong legal basis**: reinforces the evidentiary validity of records - **Applicable to sectors such as finance, health, intellectual property or logistics** ## 03 / Disadvantages - **Irreversible errors**: If a transaction is incorrectly recorded, it cannot be easily corrected - **Risk of stiffness**: systems that are too immutable can hinder legitimate updates or fixes - **Consensus dependence**: immutability can be broken if the majority of the network collaborates on a fork - **Requires robust governance** to handle exceptions without compromising overall integrity - **Does not apply to data outside the chain**, which can change even if the hash is immutable RELATED CONCEPTS [Blockchain](/en/glosario/blockchain) [Hash](/en/glosario/hash) [Smart contract](/en/glosario/smart-contract) [Smart Contract](/en/glosario/smart-contract-contrato-inteligente) [Fork (Bifurcation)](/en/glosario/fork-bifurcacion) [Node](/en/glosario/nodo) KEEP LEARNING [How to protect your digital assets in the cryptocurrency world](/en/articulos/como-proteger-tus-activos-digitales-criptomonedas) [Blockchain use cases in the supply chain.](/en/articulos/casos-de-uso-de-blockchain-en-la-cadena-de-suministro) [Tokenization without legal problems in Spain and Europe: What you need to know before you start](/en/articulos/tokenizacion-sin-problemas-legales-lo-que-debes-saber-antes-de-empezar) [Smart contracts: good practices that will save you from a hack](/en/articulos/contratos-inteligentes-bien-hechos-buenas-practicas-que-te-salvaran-de-un-hack) [What Do Blockchain Developers Do?](/en/articulos/que-hacen-los-desarrolladores-blockchain) RELATED SERVICES [Product traceability](/en/servicios/sistema-trazabilidad-de-productos) [Smart contract auditing](/en/servicios/blockchain-security-audits) [Asset tokenization](/en/servicios/tokenizacion-activos) [Web3 Development](/en/servicios/desarrollo-web3) [Blockchain consulting for companies](/en/servicios/consultoria-blockchain) [Full glossary](/en/glosario) This entry is informative. It is not legal, tax or investment advice. The rules cited change: check the current version on [BOE](https://www.boe.es) and [EUR-Lex](https://eur-lex.europa.eu).