There is notable overlap between Jainism and Buddhism, rooted in their shared Śramaṇa heritage and emphasis on renunciation and ethical living. Here are the main points of overlap and the key differences:

Overlap

• Karma and rebirth: Both traditions believe that actions produce consequences that affect future lives.
• Suffering and liberation: Both seek release from samsara and ending dukkha (Buddhism) or the cycle of birth and death (Jainism).
• Moral discipline: Both stress nonviolence and moral restraint as essential spiritual foundations.
• Renunciation and ascetic practice: Both traditions encourage renunciation of worldly ties and pursue disciplined monastic or semi-monastic paths.
• Meditation and inner transformation: Both value practices that cultivate mental clarity, ethical conduct, and detachment.

Differences (at a glance)

• Self/atman: Jainism affirms an eternal individual soul (jiva) that is bound by karma and aims for kevala jnana (omniscience) and moksha. Buddhism denies a permanent self (an atman) and teaches the cessation of all conditioned phenomena to reach nirvana.
• Karma theory: In Jainism karma is a subtle substance that literally attaches to the soul and must be shed through purification. In Buddhism karma is ethical causation that conditions future experiences but does not entail a permanent jiva (and is analyzed within dependent origination).
• Ultimate goal: Jainism seeks moksha through complete liberation of the soul and removal of karmic matter. Buddhism seeks nirvana, the cessation of craving and the ending of samsara, without asserting a soul’s true, everlasting essence.
• Cosmology and gods: Jainism involves a detailed cosmology with liberated souls (kevalins) and multiple Tirthankaras; gods exist but are not creators and are still within samsara. Buddhism generally presents a non-theistic framework and centers on the path to awakening without a creator deity.
• Ethical vows: Jainism has highly detailed vows (ahimsa, satya, asteya, brahmacharya, aparigraha, plus extensive monastic vows and, in some contexts, sallekhana). Buddhism has the Five Precepts for lay followers and additional monastic rules; its ethical framework is tied to the Four Noble Truths and the Eightfold Path.
• Scripture and lineage: Jainism revolves around the teachings of the Tirthankaras (with Mahavira as the last) and the Jain Agamas. Buddhism centers on the teachings of the Buddha (Shakyamuni) and various Buddhist canons (Tripitaka) with diverse schools (Theravada, Mahayana, Vajrayana).

If you’d like, I can point to authentic Jain sources that discuss these contrasts in more detail (and note where Digambara and Śvetāmbara views differ).