Allen mụrụ na Jenụwarị 21, 1953, na Seattle, Washington, na Kenneth Sam Allen na Edna Faye (née Gardner) Allen. Allen gara Lakeside School, ụlọ akwụkwọ nkeonwe na Seattle, ebe ọ bụ enyi nke Bill Gates dị afọ abụọ, onye ya na ya nwere mmasị na kọmputa. Ha jiri Lakeside's Teletype terminal iji zụlite nkà mmemme ha na ọtụtụ usoro kọmputa na-ekerịta oge. Ha jikwa ụlọ nyocha nke Ngalaba Sayensị Kọmputa nke Mahadum Washington, na-eme nchọpụta onwe onye na mmemme kọmputa; na ọ dịkarịa ala otu oge na 1971, a machibidoro ha n'ụlọ nyocha maka iji ihe ùgwù ha eme ihe n'ebe ahụ. Dị ka Allen si kwuo, n'oge ha dị afọ iri na ụma, ya na Bill Gates ga-aga dumpster-diving maka koodu kọmputa. Mgbe ha kwụsịrị mmemme na ịnweta SAT zuru oke nke 1600, Allen gara Ụlọ Akwụkwọ Ọzụzụ nke Washington State, bụ ebe ọ sonyeere Theta Thern, onye o kesara ịnụ ọkụ n'obi maka kọmputa.
Ụlọ akwụkwọ Harvard