{"id":13671,"date":"2026-11-06T03:17:11","date_gmt":"2026-11-06T03:17:11","guid":{"rendered":"https:\/\/aiper.com\/blogs\/?page_id=13671"},"modified":"2026-11-12T04:43:24","modified_gmt":"2026-11-12T04:43:24","slug":"parts-per-million","status":"publish","type":"page","link":"https:\/\/aiper.com\/blogs\/glossary\/parts-per-million\/","title":{"rendered":"What Is Parts Per Million?"},"content":{"rendered":"  <div class=\"aiper-glossary\" lang=\"en-US\" data-result-one=\"{count} term\" data-result-many=\"{count} terms\" data-empty=\"No terms found. Try another name or clear the filters.\">\r\n     <header><p>Pool Water Chemistry<\/p><h1>What Is Parts Per Million?<\/h1><p>Parts per million expresses a small concentration as one part of a substance per million parts of the mixture.<\/p><\/header>\r\n   <figure><picture><source media=\"(max-width:600px)\" width=\"600\" height=\"650\" srcset=\"https:\/\/aiper.com\/blogs\/wp-content\/plugins\/aiper-core\/glossary\/parts-per-million.svg?ver=0.5.11\"><img src=\"https:\/\/aiper.com\/blogs\/wp-content\/plugins\/aiper-core\/glossary\/parts-per-million.svg?ver=0.5.11\" alt=\"One enlarged purple marker in a water field represents one part of substance per million parts of mixture; approximately one milligram per liter in dilute water. Not a literal particle count.\" width=\"600\" height=\"650\" fetchpriority=\"high\" decoding=\"async\"><\/picture><figcaption>One enlarged purple marker in a water field represents one part of substance per million parts of mixture; approximately one milligram per liter in dilute water. Not a literal particle count.<\/figcaption><\/figure>\r\n   <section><h2>Understanding the Concept<\/h2><p>For dilute pool-water measurements, one part per million is approximately one milligram per liter. The approximation depends on water density.<\/p><\/section><section><h2>Common Misunderstanding<\/h2><p>The substance and reporting basis matter: calcium hardness reported as calcium carbonate is not the same as the mass of elemental calcium.<\/p><\/section>   <section><h2>Related terms<\/h2><ul><li><a data-glossary-link=\"related-term\" href=\"https:\/\/aiper.com\/blogs\/glossary\/calcium-hardness\/\">Calcium Hardness<\/a><\/li><li><a data-glossary-link=\"related-term\" href=\"https:\/\/aiper.com\/blogs\/glossary\/free-chlorine\/\">Free Chlorine<\/a><\/li><\/ul><\/section>   <section><h2>Learn more<\/h2><ul><li><a data-glossary-link=\"tool\" href=\"https:\/\/aiper.com\/blogs\/pool-chlorine-calculator\/\">Pool Chlorine Calculator<\/a><\/li><\/ul><\/section>  <\/div>\r\n  <script type=\"application\/ld+json\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@type\":\"DefinedTerm\",\"name\":\"Parts Per Million\",\"inLanguage\":\"en-US\",\"description\":\"Parts per million expresses a small concentration as one part of a substance per million parts of the mixture.\",\"url\":\"https:\\\/\\\/aiper.com\\\/blogs\\\/glossary\\\/parts-per-million\\\/\",\"inDefinedTermSet\":\"https:\\\/\\\/aiper.com\\\/blogs\\\/glossary\\\/#terms\"}<\/script>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":3,"featured_media":0,"parent":13585,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"aiper_reading_time":1,"aiper_last_reviewed":"","aiper_reviewer":0,"aiper_related_ids":[],"aiper_layout":"tool","footnotes":""},"class_list":["post-13671","page","type-page","status-publish","hentry"],"lang":"en","translations":{"en":13671,"de":13764,"fr":13813,"es":13863},"_links":{"self":[{"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/pages\/13671","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/comments?post=13671"}],"version-history":[{"count":1,"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/pages\/13671\/revisions"}],"predecessor-version":[{"id":13712,"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/pages\/13671\/revisions\/13712"}],"up":[{"embeddable":true,"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/pages\/13585"}],"wp:attachment":[{"href":"https:\/\/aiper.com\/blogs\/wp-json\/wp\/v2\/media?parent=13671"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}