Frank Tripucka has the worst career passer rating, with a 52.2 rating.

worst qb rating career
Interpreted as:
worst qb rating with a minimum of 1500 passing attempts by a player career
TripuckaPhippsDavidsonRoteKempPastoriniParilliBlandaLeBaronWaterfieldMaloneBrownPagelLivingstonTrudeauLayneMirerNamathSneadHartManningZornHadl52.252.654.956.857.359.159.660.661.461.661.962.863.363.363.363.463.565.565.566.667.167.367.4
NAMEGPRATEATTCMPPCTYDSAVGYDS/GTDTD%INTINT%SCKSCKY
Frank TripuckaFrank Tripucka7552.21,74587950.410,2825.9137.1694.01247.1
Mike PhippsMike Phipps11952.61,79988649.210,5065.888.3553.11086.01721,514
Cotton DavidsonCotton Davidson11154.91,75277043.911,7606.7105.9734.21086.2
Tobin RoteTobin Rote14956.82,9071,32945.718,8506.5126.51485.11916.6
Jack KempJack Kemp12257.33,0731,43646.721,2186.9173.91143.71836.021187
Dan PastoriniDan Pastorini14059.13,0551,55650.918,5156.1132.31033.41615.32462,229
Babe ParilliBabe Parilli18959.63,3301,55246.622,6816.8120.01785.32206.600
George BlandaGeorge Blanda34060.64,0071,91147.726,9206.779.22365.92776.91294
Eddie LeBaronEddie LeBaron13461.41,79689850.013,3997.5100.01045.81417.9
Bob WaterfieldBob Waterfield9161.61,61781450.311,8497.3130.2976.01287.9
Mark MaloneMark Malone7361.91,64883950.910,1756.2139.4603.6814.986671
Ed BrownEd Brown15462.81,98794947.815,6007.9101.31025.11386.9
Mike PagelMike Pagel13263.31,50975650.19,4146.271.3493.2634.2115837
Mike LivingstonMike Livingston9163.31,75191252.111,2956.5124.1563.2834.71521,392
Jack TrudeauJack Trudeau6763.31,64487353.110,2436.2152.9422.6694.2103717
Bobby LayneBobby Layne17563.43,7001,81449.026,7687.2153.01965.32436.6
Rick MirerRick Mirer8063.52,0431,08853.311,9695.9149.6502.4763.71991,038
Joe NamathJoe Namath14065.53,7621,88650.127,6637.4197.61734.62205.81091,052
Norm SneadNorm Snead17865.54,3532,27652.330,7977.1173.01964.52575.994744
Jim HartJim Hart20166.65,0762,59351.134,6656.8172.52094.12474.92431,936
Archie ManningArchie Manning15167.13,6422,01155.223,9116.6158.41253.41734.83963,092
Jim ZornJim Zorn14067.33,1491,66953.021,1156.7150.81113.51414.52131,585
John HadlJohn Hadl22467.44,6872,36350.433,5037.1149.62445.22685.71791,514
Jim PlunkettJim Plunkett15767.53,7011,94352.525,8827.0164.91644.41985.33803,279
Richard ToddRichard Todd11967.62,9671,61054.320,6106.9173.21244.21615.42642,127
StatMuse has season-level data for passer rating and passing attempts going back to the 1932 season.