kb/data/developer.mozilla.org/en-US/docs/Glossary/Salt-1.md

title	chunk	source	category	tags	date_saved	instance
Salt - Glossary | MDN	2/3	https://developer.mozilla.org/en-US/docs/Glossary/Salt	reference	web, html, css, javascript, documentation	2026-05-05T05:44:26.461569+00:00	kb-cron

Salt

In cryptography, salt is random data added to a password before it is hashed. This makes it impossible for an attacker to derive passwords from their hashes using precomputed tables of passwords and the corresponding hashes. Passwords should never be stored in their plaintext form, because of the risk that an attacker might break into the database where they are stored. Typically, the password is hashed, and the resulting hash is stored. If the hash function is cryptographically secure, then even if an attacker can get access to the stored hashes, it is impractical for them to reverse the function. To derive a password from a hash, attackers can look up the password corresponding to a hash in a precomputed table (also known as a rainbow table) mapping possible passwords to their hashes:

Password	Hash
pa55w0rd	56965E2A...
abcdef	BEF57EC7...
letmein	1C8BFE8F...
Although these tables may be very large, such attacks can be effective because table lookup is a fast operation. Adding random salt to passwords before hashing them stops this attack from working because the hash is not calculated based on the password alone but on the password combined with the salt. Unlike the password, the salt does not need to be kept secret: it can be stored alongside the salted and hashed password in the server's database. ## Help improve MDN
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1. Glossary
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   2. Baseline (compatibility)
   3. Baseline (typography) 33. BCP 47 language tag 34. Beacon 35. Bézier curve 36. bfcache 37. BiDi 38. BigInt 39. Binding 40. Bitwise flags 41. Blink 42. blink element ( tag) 43. Block
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   8. Boolean attribute (HTML) 47. Bounding box 48. Breadcrumb 49. Brotli compression 50. Browser 51. Browsing context 52. Buffer 53. Bun 54. Cache 55. Cacheable 56. CalDAV 57. Call stack 58. Callback function 59. Camel case 60. Canonical order 61. Canvas 62. Card sorting 63. CardDAV 64. Caret 65. CDN 66. Certificate authority 67. Certified 68. Challenge-response authentication 69. Character 70. Character encoding 71. Character reference 72. Character set 73. Chrome 74. CIA 75. Cipher 76. Cipher suite 77. Ciphertext 78. Class 79. Client-side rendering (CSR) 80. Closure 81. Cloud 82. Cloud computing 83. CMS 84. Code point 85. Code splitting 86. Code unit 87. Codec 88. Color space 89. Color wheel 90. Compile 91. Compile time 92. Composite operation 93. Compression Dictionary Transport 94. Computer programming 95. Conditional 96. Constant 97. Constructor 98. Content header 99. Continuous integration 100. Continuous media 101. Control flow 102. Cookie 103. Copyleft 104. CORS 105. CORS-safelisted request header 106. CORS-safelisted response header 107. Crawler 108. Credential 109. CRLF 110. Cross Axis 111. Cross-site request forgery (CSRF) 112. Cross-site scripting (XSS) 113. CRUD 114. Cryptanalysis 115. Cryptography 116. CSP 117. CSS 118. CSS Object Model (CSSOM) 119. CSS pixel 120. CSS preprocessor 121. Cumulative Layout Shift (CLS) 122. Data structure 123. Database 124. Debounce 125. Decryption 126. Deep copy 127. Delta 128. Denial of Service (DoS) 129. Deno 130. Descriptor (CSS) 131. Deserialization 132. Developer tools 133. Device pixel 134. Digital certificate 135. Digital signature 136. Distributed Denial of Service (DDoS) 137. DMZ 138. DNS 139. Doctype 140. Document directive 141. Document environment 142. DOM (Document Object Model) 143. Domain 144. Domain name 145. Domain sharding 146. Dominator 147. DSL
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   10. DSL (Domain-Specific Language) 148. DTLS (Datagram Transport Layer Security) 149. DTMF (Dual-Tone Multi-Frequency signaling) 150. Dynamic typing 151. ECMA 152. ECMAScript 153. Effective connection type 154. Element 155. Encapsulation 156. Encryption 157. Endianness 158. Engine
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   13. Media (Audio-visual presentation)
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