A-mtundu mabuku amanena za misa msika mapepala ndi anakonzedwa masamba a 178x111mm (osawoneka).
Mtundu wa A pepala muyezo kukula kwa misa-msika mapepala mapepala ndi 4.25 mainchesi mulifupi ndi mainchesi 7.0 kutalika, ndi pafupifupi msana m'lifupi pa 0.5 inchi. Masamba awa amapangitsa kuti bukuli likhale losavuta kuti owerenga azinyamula ndikukwanira bwino m'matumba ambiri kapena m'matumba akumbuyo.
Mabuku a A-format a mapepala amsika amsika nthawi zambiri amakhala osindikiza mabuku omwe chiyeso mainchesi 4.25 m'lifupi ndi mainchesi 7.0 ndipo ndi yaying'ono kuposa mawonekedwe a B, omwe amagwiritsidwanso ntchito ndi osindikiza malonda malonda mapepala.
Mabuku awa amasindikizidwanso ndi nyumba zazikulu zosindikizira zomwe zimakhala ndi masamba osakwana 200, omwe nthawi zambiri amafalitsidwa mochuluka - choncho dzina lawo. Mapepala ang'onoang'ono pamsika wa A-format ndi otsika mtengo kuposa chikuto cholimba mabuku ndi kupanga ndalama mwina kwa owerenga pa bajeti yolimba. Mitundu yodziwika bwino yamapepala am'misika yayikulu imaphatikizapo nkhani zachikondi ndi zinsinsi komanso zolemba zabodza, monga zolembalemba. Posachedwapa mapepala ena ogulitsidwa kwambiri apezekanso ngati mabuku amagetsi opatsa owerenga njira zambiri zowerengera zowerengera! Kuyambira kuwerenga mwachangu mpaka mabuku akale, mabuku okonda bajeti monga amene ali m’mabuku a A-format ndi opambana motsimikizirika!