Make bills in credits. According to Make's pricing page, most actions use one credit, some advanced AI features use more, and error handlers and Router modules use none. Plans (Free, Core, Pro, Teams, Enterprise) come with a monthly credit allowance; extra credits are bought in bundles and expire. Each block of credits also carries data transfer and data store limits. The effect: cost scales with modules times items times runs. A scenario that loops over 50 order lines multiplies quickly.
n8n Cloud bills by executions: one full run of a workflow counts once regardless of how many nodes it has, and plans include unlimited users and workflows, per n8n's pricing page.
Self-hosted n8n has no per-run charge for internal business use. You pay for the server, backups and whoever maintains it. That fixed cost is why self-hosting looks expensive for three small workflows and cheap for thirty busy ones.
On both tools, the larger long-term cost is people: building scenarios carefully, testing edge cases, and fixing them when a connected app changes its API.