A Mandelbrot set calculation (pure Python) ran in 0.41s on 3.13 vs. 0.58s on 3.12 – a 29% improvement.
| Benchmark (pure Python) | 3.12 | 3.13 | Δ | Notes | |------------------------|------|------|---|-------| | N-body (float loops) | 1.00x | 1.27x | +27% | JIT helps numeric ops | | JSON load/dump (large dict) | 1.00x | 1.18x | +18% | Improved dict layout | | Regex match (email extraction) | 1.00x | 1.12x | +12% | JIT + regex engine tweaks | | Startup time (import numpy ) | 1.00x | 0.93x | -7% | JIT warmup overhead | | Threaded (4 cores, GIL build) | 1.00x | 1.02x | +2% | Marginal | | Threaded (4 cores, no-GIL build) | N/A | 3.65x | N/A | Only for CPU-bound | python 3.13 release news 2025 november
While the final version of Python 3.13 originally debuted on , its impact peaked throughout 2025 as major libraries achieved full compatibility with its groundbreaking performance features. Python 3.13 Maintenance in November 2025 A Mandelbrot set calculation (pure Python) ran in 0