{"id":33475,"date":"2026-09-11T08:46:07","date_gmt":"2026-09-11T08:46:07","guid":{"rendered":"https:\/\/www.bitnovo.com\/blog\/?p=33475"},"modified":"2026-09-11T08:46:07","modified_gmt":"2026-09-11T08:46:07","slug":"real-world-applications-of-hash-functions-beyond-cryptocurrencies","status":"publish","type":"post","link":"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies","title":{"rendered":"Real-world applications of hash functions beyond cryptocurrencies"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 counter-hierarchy ez-toc-counter ez-toc-transparent ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Alternar tabla de contenidos\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #ffffff;color:#ffffff\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #ffffff;color:#ffffff\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#what_a_hash_function_does_in_a_nutshell\" >What a hash function does in a nutshell<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#passwords_why_they_are_never_stored_in_plain_text\" >Passwords: why they are never stored in plain text<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#salt_and_key_stretching_in_storage\" >Salt and key stretching in storage<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#when_a_hash_algorithm_is_considered_broken\" >When a hash algorithm is considered broken<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#file_integrity_verification\" >File integrity verification<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#digital_signatures_and_certificates\" >Digital signatures and certificates<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#databases_and_data_structures\" >Databases and data structures<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#blockchain_where_hashing_fits_into_the_entire_logic\" >Blockchain: where hashing fits into the entire logic<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.bitnovo.com\/blog\/en\/real-world-applications-of-hash-functions-beyond-cryptocurrencies\/#frequently_asked_questions_about_hash_functions\" >Frequently asked questions about hash functions<\/a><\/li><\/ul><\/nav><\/div>\n<span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Tiempo de lectura:<\/span> <span class=\"rt-time\"> 4<\/span> <span class=\"rt-label rt-postfix\">minutos<\/span><\/span><p>Behind almost everything you do on the Internet\u2014logging into a website, sending a message, making a payment, or downloading a file\u2014there is a silent protagonist:\u00a0<strong>cryptographic <a href=\"https:\/\/en.wikipedia.org\/wiki\/Hash_function\">hash functions<\/a><\/strong>. Although their use is often associated almost exclusively with Bitcoin and blockchain networks, they have been the invisible infrastructure underpinning everyday digital security for decades.<\/p>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter wp-image-32178 size-large\" src=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/06\/1-16-1024x765.jpg\" alt=\"\" width=\"1024\" height=\"765\" srcset=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/06\/1-16-1024x765.jpg 1024w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/06\/1-16-300x224.jpg 300w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/06\/1-16-768x574.jpg 768w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/06\/1-16.jpg 1328w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<p>To understand their impact, it is useful to distinguish two basic concepts: the\u00a0<strong><a href=\"https:\/\/www.bitnovo.com\/blog\/en\/what-is-a-hash-definition-function-and-security\">hash<\/a> function<\/strong>\u00a0is the mathematical algorithm, while the\u00a0<strong>hash<\/strong>\u00a0is the result obtained: a unique, fixed-length digital fingerprint that represents the processed data. Without this technology, ensuring privacy, authenticity, and integrity of information on the network would be practically impossible.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"what_a_hash_function_does_in_a_nutshell\"><\/span><strong>What a hash function does in a nutshell<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>It transforms any set of input data into a\u00a0<strong>fixed-length string of characters<\/strong>, in a deterministic and practically irreversible manner.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"passwords_why_they_are_never_stored_in_plain_text\"><\/span><strong>Passwords: why they are never stored in plain text<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>When you register for a web service, a serious platform never stores your password as you type it. Instead, the system calculates the\u00a0<strong><a href=\"https:\/\/fastercapital.com\/es\/tema\/aplicaciones-de-funciones-hash-m%C3%A1s-all%C3%A1-de-la-criptograf%C3%ADa.html\">hash<\/a> of your password<\/strong>\u00a0and stores only that resulting string.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-33476 size-full\" src=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/2-6.jpg\" alt=\"\" width=\"612\" height=\"283\" srcset=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/2-6.jpg 612w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/2-6-300x139.jpg 300w\" sizes=\"(max-width: 612px) 100vw, 612px\" \/><\/p>\n<p>Each time you log in, the server reapplies the hash function to the entered password and compares the result with the stored value. If they match, access is granted. This method ensures that, even if the database is compromised by a cyberattack or reviewed by technical staff,\u00a0<strong>the original passwords remain hidden<\/strong>.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"salt_and_key_stretching_in_storage\"><\/span><strong>Salt and key stretching in storage<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>To prevent attackers from guessing passwords using dictionaries or precomputed hash lists, systems apply a\u00a0<strong>salt<\/strong>: a unique random string added to the password before processing it.<\/p>\n<p>In this way, two users with the same password will generate\u00a0<strong>completely different hashes<\/strong>. In addition,\u00a0<strong>key stretching<\/strong>\u00a0techniques are used, via algorithms designed to be deliberately slow and resource-demanding (such as Argon2, bcrypt, or scrypt), making large-scale brute-force attacks more difficult.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"when_a_hash_algorithm_is_considered_broken\"><\/span><strong>When a hash algorithm is considered broken<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>An algorithm is considered\u00a0<strong>cryptographically broken<\/strong>\u00a0when\u00a0<strong>practical collisions<\/strong>\u00a0are discovered\u2014that is, when two completely different input data sets generate the same output <a href=\"https:\/\/www.bbva.com\/es\/innovacion\/de-la-verificacion-de-contrasena-a-la-firma-electronica-el-secreto-esta-en-el-hash\/\">hash<\/a>.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-33477 size-large\" src=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-1024x683.jpg\" alt=\"\" width=\"1024\" height=\"683\" srcset=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-1024x683.jpg 1024w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-300x200.jpg 300w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-768x512.jpg 768w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-1536x1024.jpg 1536w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/3-6-2048x1365.jpg 2048w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<p>Historical cases like MD5 or SHA-1 showed these weaknesses over time. In 2017, SHA-1&#8217;s vulnerability was demonstrated by generating\u00a0<strong>two different PDF files with an identical hash<\/strong>. When this happens, industry standards\u00a0<strong>discard the algorithm<\/strong>\u00a0and replace it with robust alternatives such as the SHA-2 family (<a href=\"https:\/\/www.bitnovo.com\/blog\/en\/what-is-sha-256-algorithm-and-how-does-it-work\">SHA-256<\/a>) or SHA-3.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"file_integrity_verification\"><\/span><strong>File integrity verification<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>When you download software, system images, or critical updates, providers often publish the\u00a0<strong>official hash value<\/strong>\u00a0of the file. By calculating the hash of your download locally and comparing it with the published one, you can instantly validate that the file has not been corrupted during transfer or maliciously altered.<\/p>\n<ul>\n<li><strong>Downloads verified with SHA-256<\/strong>: This is the current standard for checking the authenticity of software distributed over the network.<br \/>\n\u2022\u00a0<strong>Duplicate detection in storage<\/strong>: Cloud services and enterprise file systems use hashes to identify identical files, saving storage space without needing to read the full content of each document.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"digital_signatures_and_certificates\"><\/span><strong>Digital signatures and certificates<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>In electronic document signing and SSL\/TLS security certificates that protect websites, processing large files with cryptographic keys is inefficient. The solution is to first calculate the\u00a0<strong>hash of the document or certificate<\/strong>\u00a0and apply the digital signature\u00a0<strong>only to that digest<\/strong>.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-33478 size-full\" src=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/4-1.jpg\" alt=\"\" width=\"612\" height=\"282\" srcset=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/4-1.jpg 612w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2026\/09\/4-1-300x138.jpg 300w\" sizes=\"(max-width: 612px) 100vw, 612px\" \/><\/p>\n<p>If an attacker modifies even a single bit of the original document, the resulting hash changes completely and the digital signature is\u00a0<strong>immediately invalidated<\/strong>, ensuring\u00a0<strong>non-repudiation and authenticity<\/strong>.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"databases_and_data_structures\"><\/span><strong>Databases and data structures<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Outside the security field, hash functions are\u00a0<strong>fundamental pillars<\/strong>\u00a0of software development. Structures such as\u00a0<strong>hash tables<\/strong>\u00a0or\u00a0<strong>dictionaries<\/strong>\u00a0allow keys to be associated with values via a derived numeric index. This enables\u00a0<strong>near-instantaneous<\/strong>\u00a0searching, insertion, and retrieval of data, optimizing the performance of search engines, databases, and large-scale indexing systems.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"blockchain_where_hashing_fits_into_the_entire_logic\"><\/span><strong>Blockchain: where hashing fits into the entire logic<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>In <a href=\"https:\/\/www.bitnovo.com\/blog\/en\/hash-blockchain-detect-real-content\">blockchain<\/a> networks, hashing is the mechanism that ensures the\u00a0<strong>immutability of the ledger<\/strong>. Each block in the network contains a set of transactions synthetically organized via\u00a0<strong>Merkle trees<\/strong>, the hash of the previous block&#8217;s header, and a random value.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-26556 size-large\" src=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2023\/01\/Codigo-Programacion-Hackear-1024x682.jpg\" alt=\"\" width=\"1024\" height=\"682\" srcset=\"https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2023\/01\/Codigo-Programacion-Hackear-1024x682.jpg 1024w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2023\/01\/Codigo-Programacion-Hackear-300x200.jpg 300w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2023\/01\/Codigo-Programacion-Hackear-768x512.jpg 768w, https:\/\/www.bitnovo.com\/blog\/wp-content\/uploads\/2023\/01\/Codigo-Programacion-Hackear.jpg 1280w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<p>By including the digital fingerprint of the previous block in the new block, an\u00a0<strong>inseparable mathematical chain<\/strong>\u00a0is generated: if someone tried to alter even a single past transaction, that block&#8217;s hash would change,\u00a0<strong>breaking the continuity<\/strong>\u00a0of the entire subsequent chain and making the tampering attempt evident.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"frequently_asked_questions_about_hash_functions\"><\/span><strong>Frequently asked questions about hash functions<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul>\n<li><strong>Can a hash be reversed?<\/strong>No. It is a strictly\u00a0<strong>one-way<\/strong>\u00a0process.<br \/>\n\u2022\u00a0<strong>What is the difference between MD5, SHA-1, and SHA-256?<\/strong>\u00a0MD5: 128 bits, broken by collisions. SHA-1: 160 bits, obsolete and insecure. SHA-256: 256 bits, current and secure standard.<br \/>\n\u2022\u00a0<strong>Why is SHA-256 still considered secure?<\/strong>\u00a0Because of the\u00a0<strong>vastness of its key space<\/strong>. There are no known collisions nor computing power capable of breaking it.<br \/>\n\u2022\u00a0<strong>Can quantum computing break current hashes?<\/strong>\u00a0It does not break them. Grover&#8217;s algorithm reduces their security by half, which is still\u00a0<strong>unattainable<\/strong>\u00a0for current technology.<br \/>\n\u2022\u00a0<strong>Are hashing and encryption the same?<\/strong>\u00a0No. Encryption is\u00a0<strong>bidirectional<\/strong>, hashing is\u00a0<strong>unidirectional and irreversible<\/strong>.<\/li>\n<\/ul>\n<p>Hash functions are the\u00a0<strong>invisible foundations<\/strong>\u00a0that sustain trust in the digital world. Although they operate silently behind every stored password, electronic signature, or network transaction, they are the guarantee that information travels\u00a0<strong>secure, intact, and tamper-free<\/strong>.<\/p>\n<p>In short, understanding hashing is not just for experts: it is knowing the\u00a0<strong>invisible digital fingerprint<\/strong>\u00a0that protects our daily lives on the Internet.<\/p>\n","protected":false},"excerpt":{"rendered":"<p><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Tiempo de lectura:<\/span> <span class=\"rt-time\"> 4<\/span> <span class=\"rt-label rt-postfix\">minutos<\/span><\/span>Hash functions are in your passwords, your downloads, and your digital signatures. Where they are really used beyond the crypto world.<\/p>\n","protected":false},"author":12,"featured_media":33470,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[185],"tags":[],"class_list":["post-33475","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blockchain-en"],"_links":{"self":[{"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/posts\/33475","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/comments?post=33475"}],"version-history":[{"count":2,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/posts\/33475\/revisions"}],"predecessor-version":[{"id":33710,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/posts\/33475\/revisions\/33710"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/media\/33470"}],"wp:attachment":[{"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/media?parent=33475"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/categories?post=33475"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bitnovo.com\/blog\/wp-json\/wp\/v2\/tags?post=33475"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}