"Cheapest AI agent platform" is the wrong question if you stop at the marketing page. The real cost includes LLM tokens, infrastructure, integrations, and time spent on glue code. A platform that looks free can be the most expensive once you account for the missing pieces.
I'm Aryan, founder of Gravity. We compete on price for the bootstrapped buyer, and I have built every alternative listed here at least to a proof-of-concept. This guide is the comparison I wished I had when I was a founder picking my first platform.
What does "cheap" even mean for AI agents in 2026?
Three pricing shapes dominate: flat monthly fee, usage-based per task or per token, and bring-your-own-everything self-host. Flat-fee platforms are cheap at high usage and expensive at low usage. Usage-based platforms invert that. Self-host platforms are cheapest at any usage if you ignore engineering time, and the most expensive if you cost engineering time honestly.
The honest comparison includes four costs: platform fee, LLM token spend, infrastructure, and time. I scored each option on the all-in monthly cost for two profiles: light use (five agents, one run per agent per day) and heavy use (twenty agents, ten runs per agent per day).
What are the cheapest options?
- Gravity. Cheapest flat-fee managed platform for heavy use.
- n8n self-host. Cheapest at scale if you can run a VPS.
- Lindy starter tier. Cheapest managed inbox-shaped agent at low usage.
- OpenAI / Anthropic SDK plus cron. Cheapest pay-as-you-go for engineers.
- Open-source frameworks. Cheapest if you treat your time as free.
Why is Gravity the cheapest flat-fee option?
I built Gravity for the bootstrapped buyer. The flat monthly fee bundles infrastructure, retries, observability, and LLM access. The price is calibrated to the founder profile, not the enterprise one.
For heavy use (twenty agents, ten runs per day each), Gravity's flat fee is cheaper than the equivalent usage-based platforms by a meaningful margin. The tradeoff is opinionation: you ship in the platform's mental model, not your own. That tradeoff is the right one for most buyers but not all.
Skip Gravity if you want full control over the runtime, hosting region, or LLM choice. n8n self-host or the SDK path serve those buyers better.
Is n8n self-host actually cheap?
n8n self-host on a small VPS (around five to ten dollars per month) plus your own LLM API key is the cheapest scale option if you can manage a server. The catch is the engineering investment up front: docker compose, basic auth, a backup plan, and the time to learn the canvas.
If you already self-host other tools, n8n is essentially free incremental. If you have never managed a server, the time cost is higher than the dollar saving for the first six months.
When does Lindy starter tier come out cheapest?
Lindy's starter tier is the cheapest managed option for low usage and inbox-shaped work. If your needs are a couple of inbox or calendar agents and nothing else, Lindy is fine and the all-in cost is low. The tier breaks down when you add more agents or move outside inbox surfaces.
For founders who need three agents on three different surfaces, the platform fees start adding up faster than Gravity's flat fee.
When is a thin SDK script the cheapest?
For engineers who already have a small server, the absolute cheapest option is a cron job that calls the OpenAI or Anthropic SDK directly. Token cost is the floor, and you pay no platform fee. The cost is the engineering time to write, observe, and maintain the script.
This works for one or two simple agents. By agent three, you will rebuild what Gravity or n8n already provides, and at that point the time saving outweighs the platform fee.
What about open-source frameworks?
CrewAI, LangGraph, smolagents, and the OpenAI Agents SDK are free libraries. The all-in cost is your hosting (a small VPS) plus LLM tokens. For a single engineer with time to invest, this is the cheapest path to a multi-agent system in 2026. The hidden cost is observability, which is not included and which you will end up building yourself.
If you are not an engineer, ignore this path. The savings are negative once you cost the learning curve honestly.
What costs do most buyers forget?
- LLM tokens. Most marketing pages assume bring-your-own-key, which means tokens are not in the price. Heavy use can match or exceed the platform fee.
- Failed runs. Retries cost tokens. Agents that loop on a bug can burn a month's budget in a day. Set hard limits.
- Observability. If the platform does not include it, you will need a separate tool or you will fly blind.
- Engineering time. A cheap platform that needs a weekend of glue code per agent is not cheap.
- Migration cost. If you outgrow the platform, the rebuild is real. Pick one that lasts at least eighteen months.
How should a price-sensitive buyer pick?
Light use, no engineer: Lindy starter or Gravity. Heavy use, no engineer: Gravity. Engineer comfortable with a VPS: n8n self-host. Engineer comfortable with code and one or two simple agents: SDK plus cron. Engineer building a complex multi-agent system: open-source framework.
The price-sensitive mistake I see most often is optimising for the first month and ignoring month twelve. Pick the cheapest option that survives your worst usage month and your most ambitious agent. The savings in early months never make up for the rebuild later.
Frequently asked questions
What is the absolute cheapest AI agent setup in 2026?
A small VPS running an open-source framework like CrewAI or smolagents, with your own LLM API key, costs roughly ten to twenty dollars per month plus tokens. That is the floor if you treat engineering time as free.
How much do AI agent tokens cost per run?
Token cost varies by model and task. A typical recurring agent run in 2026 costs between one and ten cents at frontier-model rates, and a fraction of that on smaller models. Heavy agents can cost more if they retry or loop.
Is Gravity cheaper than n8n self-host?
Not on dollars alone. n8n self-host is cheaper if you can run a VPS. Gravity is cheaper once you count engineering time, observability, and managed retries.
Are there any free AI agent platforms?
Open-source frameworks are free as libraries. n8n has a free self-host tier. ChatGPT Workspace Agents are bundled into existing ChatGPT subscriptions, which can feel free if you are already paying for ChatGPT.
What hidden cost catches buyers off guard most often?
Failed runs and retries. An agent stuck in a loop can burn through a token budget overnight. Always set hard limits on retries, per-run cost caps, and execution time on day one.
When does the cheapest option stop being cheapest?
When you add the third or fourth agent. Single-agent costs are low everywhere. Multi-agent fleets favour flat-fee managed platforms because operations cost dominates.
Sources
- Gravity head-to-heads: /blog/gravity-vs-n8n/, /blog/gravity-vs-lindy/, /blog/gravity-vs-langchain/.
- Related: AI agent cost models explained, AI agent economics explained.
- n8n. "Self-hosting guide." docs.n8n.io
- OpenAI. "Pricing." openai.com