İdrarın %91 ila %96'sı sudan oluşur. Geriye kalan bileşenleri arasında inorganik tuzlar, üre, organik bileşikler ve organik amonyum tuzları yer alır. Üre, katı maddelerin yaklaşık yarısını oluşturur.<ref name="RoseParker20152">{{citeAkademik journaldergi kaynağı|titlebaşlık=The Characterization of Feces and Urine: A Review of the Literature to Inform Advanced Treatment Technology|issuesayı=17|pagessayfalar=1827–18791827-1879|journaldergi=Critical Reviews in Environmental Science and Technology|yearyıl=2015|volumecilt=45|issn=1064-3389|pmc=4500995|pmid=26246784|doi=10.1080/10643389.2014.1000761|last1soyadı1=Rose|first1ad1=C.|last2soyadı2=Parker|first2ad2=A.|last3soyadı3=Jefferson|first3ad3=B.|last4soyadı4=Cartmell|first4ad4=E.|doi-access=free}} [[FileDosya:CC-BY_icon.svg|50x50pik]] Text was copied from this source, which is available under a [[creativecommons:by/4.0/|Creative Commons Attribution 4.0 International License]] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/|date=2017-10-16}}.</ref> Ortalama [[PH|pH değeri]] 6,2 olan hafif [[Asit|asid]]ik idrarın sağlıklı bir insanda değeri 5,5 ile 7 arasında değişebilir.<ref name="RoseParker2015">{{citeAkademik journaldergi kaynağı|titlebaşlık=The Characterization of Feces and Urine: A Review of the Literature to Inform Advanced Treatment Technology|issuesayı=17|pagessayfalar=1827–18791827-1879|journaldergi=Critical Reviews in Environmental Science and Technology|yearyıl=2015|volumecilt=45|issn=1064-3389|pmc=4500995|pmid=26246784|doi=10.1080/10643389.2014.1000761|last1soyadı1=Rose|first1ad1=C.|last2soyadı2=Parker|first2ad2=A.|last3soyadı3=Jefferson|first3ad3=B.|last4soyadı4=Cartmell|first4ad4=E.|doi-access=free}} [[FileDosya:CC-BY_icon.svg|50x50pik]] Text was copied from this source, which is available under a [[creativecommons:by/4.0/|Creative Commons Attribution 4.0 International License]] {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/|date=2017-10-16}}.</ref> İdrarın rengi vücudun su seviyesi, alınan besin ve hastalıklara göre değişebilir. İdrara rengini veren birincil madde [[Ürobilin|ürobilindir]].
İdrar sanılanın aksine [[steril]] değildir. Yapılan araştırmalara göre idrarda idrar kesesindeyken bile bakteri varlığı tespit edilmiştir.<ref>{{citeAkademik journaldergi kaynağı|titlebaşlık=Urine Is Not Sterile: Use of Enhanced Urine Culture Techniques To Detect Resident Bacterial Flora in the Adult Female Bladder|datetarih=26 DecemberAralık 2013|issuesayı=3|pagessayfalar=871–876871-876|journaldergi=Journal of Clinical Microbiology|volumecilt=52|pmc=3957746|pmid=24371246|doi=10.1128/JCM.02876-13|lastsoyadı=Hilt|firstad=Evann E.|author2yazar2=Kathleen McKinley|author3yazar3=Meghan M. Pearce|author4yazar4=Amy B. Rosenfeld|author5yazar5=Michael J. Zilliox|author6yazar6=Elizabeth R. Mueller|author7yazar7=Linda Brubaker|author8yazar8=Xiaowu Gai|author9yazar9=Alan J. Wolfe|author10yazar10=Paul C. Schreckenberger}}</ref><ref>{{citeAkademik journaldergi kaynağı|titlebaşlık=Urine Is Not Sterile: Use of Enhanced Urine Culture Techniques To Detect Resident Bacterial Flora in the Adult Female Bladder|datetarih=26 DecemberAralık 2013|issuesayı=3|pagessayfalar=871–876871-876|journaldergi=Journal of Clinical Microbiology|volumecilt=52|pmc=3957746|pmid=24371246|doi=10.1128/JCM.02876-13|lastsoyadı=Hilt|firstad=Evann E.|author2yazar2=Kathleen McKinley|author3yazar3=Meghan M. Pearce|author4yazar4=Amy B. Rosenfeld|author5yazar5=Michael J. Zilliox|author6yazar6=Elizabeth R. Mueller|author7yazar7=Linda Brubaker|author8yazar8=Xiaowu Gai|author9yazar9=Alan J. Wolfe|author10yazar10=Paul C. Schreckenberger}}</ref><ref name=":2">{{CiteAkademik journaldergi kaynağı|titlebaşlık=Microbial evaluation and public health implications of urine as alternative therapy in clinical pediatric cases: health implication of urine therapy|datetarih=2010-05-25 Mayıs 2010|pagessayfalar=12|journaldergi=The Pan African Medical Journal|volumecilt=5|issn=1937-8688|pmc=3032614|pmid=21293739|doi=10.4314/pamj.v5i1.56188|last1soyadı1=Ogunshe|first1ad1=Adenike Adedayo O.|last2soyadı2=Fawole|first2ad2=Abosede Oyeyemi|last3soyadı3=Ajayi|first3ad3=Victoria Abosede}}</ref>
