In Jainism, harming any living being binds karma. Insects and animals both have jiva (soul), so killing them affects one’s karma. The key factors are intention, violence, and awareness, not merely the size or species of the life form.

• Insects: Their life is delicate and many Jain taught to avoid harming them. Deliberate killing of even tiny creatures accrues negative karma, though the impact is generally smaller per act than killing a large, conscious animal, because the life-form is often considered to be at a subtler level of consciousness. Still, intentional harm is not discouraged.
• Animals: Killing animals is also binding of negative karma, typically viewed as more serious because animals are often more complex and capable of suffering more, and the act is seen as greater violence.

Both Digambara and Śvetāmbara traditions emphasize ahimsa (non-violence) to all living beings. There are differences in emphasis or ritual detail between the two traditions, but the core teaching remains: every act of killing increases karmic bondage, with greater harm resulting from greater intent, violence, or suffering caused.

If you want a concise, traditional reference on this topic, you can read more here