{"id":"eosinophils-percent","name":"Eosinophils (Percent)","shortName":"Eosinophils (%)","aliases":["EOSINOPHILS","Eosinophils %","Eos","Eos %","Eos%","Eosinophil Percent","Eosinófilos %","Eosinophile %","Eosinophils, Percent","Eosinophil %","Eosinophils (%)","Eosinophils Percent","% Eosinophils","Eosinophils Relative","Eosinophils Relative Percent","Eos (%)","Eosinophils/100 leukocytes","Eosinophils/Leukocytes","EOS PCT"],"abbreviations":["EO%","Eos%"],"loinc":[{"code":"713-8","primary":true},{"code":"714-6","primary":false},{"code":"26450-7","primary":false},{"code":"71679-5","primary":false}],"specimen":"whole-blood","units":[{"ucum":"%","display":"%"},{"ucum":"1","display":"fraction (0–1)"}],"referenceRanges":[{"population":"Adults","low":0.4,"high":6.7,"unit":"%","unitDisplay":"%","note":"ARUP interval for all ages. Labcorp does not set a range for the percent ('Not Estab.' on its reports) and Mayo reports absolute counts only. A classic textbook table gives 0.3 to 5, and MedlinePlus lists about 1 to 4. A low or zero percent is common and seldom meaningful on its own, and steroid medicines lower it within days. Eosinophilia is defined by the absolute count, not the percent.","sources":[{"title":"CBC with Platelet Count and Automated Differential (test 0040003), hotline effective March 1, 2021: reference intervals","url":"https://ltd.aruplab.com/api/ltd/hotline/0040003/44232","publisher":"ARUP Laboratories","year":2021},{"title":"Normal Values for Leukocyte Concentration in Blood (Table 63-1)","url":"https://download.skyscape.com/download/ota/lonestar/76CD77F7-898A-4928-AE45-A3D54D0FF0F0/harrisons.ed19/content/HTML/c/tu13.htm","publisher":"Harrison's Principles of Internal Medicine, 19th edition (McGraw-Hill)","year":2015},{"title":"Blood differential test","url":"https://medlineplus.gov/ency/article/003657.htm","publisher":"MedlinePlus Medical Encyclopedia (National Library of Medicine)","year":2025},{"title":"Sample patient report, test 005013 (CBC with Diff, Platelet, NLR)","url":"https://files.labcorp.com/testmenu-d8/sample_reports/005013.pdf","publisher":"Labcorp"},{"title":"French guidelines for the etiological workup of eosinophilia and the management of hypereosinophilic syndromes","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC10148979/","publisher":"Orphanet Journal of Rare Diseases","year":2023},{"title":"Blood basophil numbers in chronic ordinary urticaria and healthy controls: diurnal variation, influence of loratadine and prednisolone and relationship to disease activity","url":"https://pubmed.ncbi.nlm.nih.gov/12614448/","publisher":"Clinical and Experimental Allergy","year":2003},{"title":"Eosinophil count - absolute","url":"https://medlineplus.gov/ency/article/003649.htm","publisher":"MedlinePlus Medical Encyclopedia (National Library of Medicine)","year":2025}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"The share of your white blood cells that are eosinophils, a cell type involved in allergies and in fighting some parasites.","url":"https://bloodtesttracker.com/markers/eosinophils-percent","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}