"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.

Gravity competes on price for the bootstrapped buyer, starting with a free tier. This guide compares the genuinely cheap options on all-in cost, not just the headline number, so a first platform choice holds up well past month one.

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. Each option below is scored on 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). The table summarises where each one wins.

OptionAll-in cost, light useAll-in cost, heavy useSetup effortBest for
GravityFree tier ($0, 1 agent)One predictable plan from $20/mo, usage includedMinutesNon-engineers who want results, not a server
n8n self-host~$5-10/mo VPS + tokens~$5-10/mo VPS + tokensHigh (run a server)Engineers comfortable with a VPS
Lindy starterFrom $49.99/mo (per lindy.ai)Climbs past $49.99/mo as agents or surfaces are addedLowA couple of inbox or calendar agents
OpenAI/Anthropic SDK + cronTokens only (~1-10 cents/run)Tokens + your maintenance timeMedium (write code)Engineers running one or two simple agents
Open-source framework~$10-20/mo VPS + tokens~$10-20/mo VPS + tokensHigh (build and observe)Engineers building a complex multi-agent system
All-in cost includes platform fee, LLM tokens, infrastructure, and engineering time.

A worked example makes the difference concrete. Take five light agents, one run each per weekday, around 150 runs a month. On a self-hosted SDK script the bill is tokens only, roughly two to five dollars at small-model rates, plus the hours to write and babysit it. On n8n self-host it is the same tokens plus a five to ten dollar VPS, plus server upkeep. On Gravity the same five agents start on the free tier, then sit inside a single plan from $20 a month with usage included, and there is no server, no glue code, and no surprise token bill. For light, no-engineer use the free tier is genuinely the cheapest way to start; for heavy use the predictable plan wins on total cost once operations are counted. For the full model, see AI agent pricing explained.

What are the cheapest options?

Why is Gravity the cheapest managed way to start?

Gravity is built for the bootstrapped buyer. It starts free ($0/month, one agent), then moves to predictable plans from $20/month with usage included, and the price covers infrastructure, retries, observability, and LLM access. You can buy extra usage beyond your plan when you need it.

Gravity's edge for the price-sensitive buyer is a free starting point and a predictable bill. You begin on the free tier and move to a plan only when you need more, and the monthly price already covers the server, retries, observability, and LLM access that the cheaper-looking options either bill separately or make you build. There are no engineer hours spent on glue code, and expert-built agents are ready in about sixty seconds. 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 self-hosted Community edition is free to run under n8n's sustainable-use license, according to docs.n8n.io, so the real cost is the VPS and your token bill. 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. Its entry Plus plan starts at $49.99 per month with a 7-day trial and no free plan, according to lindy.ai's published pricing as of July 2026. 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 buyers who need three agents on three different surfaces, the per-platform fees start adding up faster than a single Gravity plan that already covers them.

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?

How should a price-sensitive buyer pick?

The price-sensitive mistake we 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

Which is the cheapest AI agent?

The cheapest managed AI agent platform is Gravity: the free tier runs one agent at $0 per month, and paid plans start at $20 per month with $20 of usage included. If you can run your own server, self-hosted n8n is cheaper at scale, and engineers can go cheaper still with a thin SDK script.

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 managed platforms because operations cost dominates, and a platform like Gravity folds those operations into one predictable plan rather than charging for idle capacity or separate tools.

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