Python 3 versus Java fastest programs Always look at the source code. These are only the fastest programs. Look at the other programs. They may seem more-like a fair comparison to you. pidigits source secs mem gz busy cpu load Python 3 3.47 10,356 386 3.53 1% 1% 0% 100% Java 3.07 39,320 938 3.31 2% 5% 3% 98% regex-redux source secs mem gz busy cpu load Python 3 18.45 457,340 512 37.52 69% 37% 50% 48% Java 10.31 644,560 740 31.47 72% 72% 92% 70% reverse-complement source secs mem gz busy cpu load Python 3 16.93 1,777,852 434 17.58 78% 21% 4% 0% Java 3.16 712,368 2183 7.08 65% 47% 42% 70% k-nucleotide source secs mem gz busy cpu load Python 3 72.24 199,856 1967 275.38 94% 94% 96% 96% Java 9.33 447,976 1812 29.36 73% 83% 82% 77% binary-trees source secs mem gz busy cpu load Python 3 80.30 448,004 589 286.50 95% 87% 87% 88% Java 8.32 953,620 835 28.37 95% 87% 81% 77% fasta source secs mem gz busy cpu load Python 3 63.55 844,180 1947 129.71 40% 71% 33% 61% Java 2.22 45,172 2473 5.99 61% 50% 98% 60% fannkuch-redux source secs mem gz busy cpu load Python 3 534.40 47,236 950 2,104.05 99% 97% 99% 99% Java 14.33 34,888 1282 56.56 99% 98% 99% 98% mandelbrot source secs mem gz busy cpu load Python 3 259.50 48,192 688 1,036.70 100% 100% 100% 100% Java 6.83 79,108 796 26.86 97% 99% 99% 99% n-body source secs mem gz busy cpu load Python 3 865.18 8,176 1196 874.96 2% 20% 79% 0% Java 21.93 35,408 1429 22.44 1% 0% 100% 1% spectral-norm source secs mem gz busy cpu load Python 3 169.87 49,188 417 675.02 100% 99% 99% 99% Java 4.22 36,948 950 16.43 98% 97% 98% 96% Python 3 Python 3.8.0 Java openjdk 13 2019-09-17 OpenJDK Runtime Environment (build 13+33) OpenJDK 64-Bit Server VM (build 13+33, mixed mode, sharing) all Python 3 programs & measurements all Java programs & measurements