The reticulated python is the longest living snake. Adults commonly reach four to six metres, and specimens above seven metres are documented from wild populations in Indonesia and Malaysia. The most frequently cited maximum, a snake taken in Sulawesi in the early twentieth century, was reported at about ten metres, though the measurement was not preserved for later checking.
Length is not the same as bulk. The green anaconda is shorter but far heavier, and a reticulated python of comparable length weighs considerably less. The python's proportions favour reach and climbing; young individuals are strongly arboreal and only become mostly terrestrial as their mass increases.
The persistent problem is measurement. A snake skin can be stretched by a fifth or more during removal and drying, so skin-based records are systematically inflated. Claims of snakes far beyond ten metres circulate regularly and have never survived verification, including a long-standing cash prize offered for a live specimen over about nine metres that was never collected.