Vibe coding for free: what you can do without money and what comes next

The query "vibe coding for free" is understandable: you want to try it without spending money. The honest answer has two parts. You can start completely free, but every such option has limits. And when those limits begin to get in the way, switching to pay-per-token costs far less than many think if you pick an inexpensive model. Below we go through the options and do the arithmetic.

If the topic is new to you, start with vibe coding: what it is and what an hour of agent work costs↗.

What "free" really means

Somebody pays for computation on servers. So "free" almost always means one of four things.

1. Free tiers and trial periods of services

Many services give limited free access: a small number of requests, cut-down models, a queue. The terms of such plans change and we do not know their current values, so we give no figures. Check the service's own pricing page before relying on it. The downsides are typical: limits run out mid-task, and the model may be weaker than in the paid version.

2. Local models on your own computer

The model runs on your machine and you do not pay for tokens. But you pay in other ways: you need a suitable GPU or a lot of RAM, and large models run slowly on an ordinary laptop or do not run at all. Whether a small local model can handle agent work (editing several files, running tests), test on your own tasks. For learning and experiments it is a workable option; more in local model or API↗.

3. Free tools

The coding app itself can cost nothing. For example, many terminal agents and editor extensions (aider, Cline, Kilo Code, opencode and others) are distributed free of charge; check each one's license in its repository. But they need a model, and the model is either local or paid via API. So the tool is free, the tokens are not.

4. A small starting balance

Zukko has no welcome credit. There is a one-time $0.50 bonus for subscribing to the @zukkopro channel: once per Telegram account (link Telegram in the dashboard, subscribe, press "Check"). This is not free access but a small entry that, with the right model choice, is enough for a trial. Below we calculate how many hours $1 buys; for $0.50, halve the result.

What an hour of vibe coding costs on a cheap model

Take a hypothetical agent session where you describe a task and the agent edits code. Assumptions for the calculation (an illustration; your numbers will differ):

• 40 model requests per hour;
• on average 25,000 input tokens per request (instruction, history, file pieces), so 40 × 25,000 = 1,000,000 tokens (1M) in total;
• 1,000 output tokens per request, 40,000 in total;
• cache is not counted: all input is priced as regular input (with caching the total is usually lower, but for Claude a cache write costs more than regular input).

Zukko prices at October 18, 2026, $ per 1M tokens (input / output):

*44 hours is about two hours a day over 22 working days.

Checking one row: for deepseek-v4.1-flash, input 1M × 0.013 = $0.013, output 0.04M × 0.038 = $0.00152, sum $0.01452. Month: 44 × 0.01452 = $0.639.

The result: an hour on the cheapest model costs from about one and a half to four cents, and on stronger ones tens of cents. Prices differ by tens of times, but the models are not the same either: the cheap ones score lower on the Intelligence Index (39 for deepseek-v4.1-flash and 42 for glm-5.3-flash against 52 for gpt-6.1-sol and 48 for claude-sonnet-5-5), and on hard tasks they may fall short. Test on your own tasks.

How far the minimum $1 top-up goes

Under the same assumptions:

• on deepseek-v4.1-flash: 1 / 0.01452 ≈ 69 hours;
• on glm-5.3-flash: 1 / 0.0416 ≈ 24 hours;
• on gpt-6.1-sol: 1 / 0.3228 ≈ 3 hours.

This is price arithmetic, not a promise: real sessions can be longer and costlier, especially if the context is bloated or the agent loops. But the order of magnitude shows that you can "try" for pennies if you do not start with the most expensive model.

How to connect a cheap model to a tool

Any model in the catalogue can be used in either format. For Claude Code, environment variables are enough:

export ANTHROPIC_BASE_URL=https://api.zukko.pro
export ANTHROPIC_AUTH_TOKEN=fetch_your_key
export ANTHROPIC_MODEL=deepseek-v4.1-flash
claude

For tools that work with an OpenAI-compatible API the address is different: https://api.zukko.pro/v1. Do not mix them up: Claude Code and the official Anthropic SDK append /v1 themselves, so they need the address without it, while clients built on the OpenAI SDK need it included. Instructions: Claude Code↗; the current model list and prices come from GET https://api.zukko.pro/v1/models or the "Models" page in the dashboard. If your tool is not described here, check its own documentation: you need the section on a custom OpenAI-compatible provider.

How not to spend more than you intended

Vibe coding is risky precisely because an agent makes many steps without your supervision. Three simple safeguards:

1. A key limit. Create a separate key for experiments with a daily limit, for example $1. Then even a looping agent stops. How to do it: a limit on an API key↗.
2. A model list for the key. Allow the key only cheap models (allowed_models) so you do not accidentally run a session on an expensive one.
3. Short sessions. The longer the history, the more input tokens at each step. Start a new session for a new task and commit to git after each working step.

Do not put secrets, passwords or keys from .env in prompts. Vibe coding does not need them.

When to move to a stronger model

A "ladder" approach works best:

1. Start with the cheapest model on simple tasks: layout, small scripts, boilerplate.
2. If the agent fails two or three times in a row, switch to a stronger model for that task only.
3. Go back to the cheap one for routine work.

How to top up

The balance is in dollars, topped up from $1. Access from Russia goes through the gateway. Payment: SBP (rubles at the market rate, the payment page adds an 8.5% fee on top), a MasterCard card (a fee of about 13%, amounts from $2 to $594) or cryptocurrency. There is no subscription: you pay only for tokens. Create the key in the dashboard↗.

FAQ

Can I do vibe coding completely free?

You can start on the free plans of services or on a local model, but they have limits: quotas, speed, quality. Check plan terms on the services' own sites; they change.

What is the cheapest model in Zukko?

At October 18, 2026 it is deepseek-v4.1-flash ($0.013 input, $0.038 output per 1M tokens), followed by glm-5.3-flash ($0.04 and $0.04). The current list comes from GET /v1/models.

Is a cheap model enough for a serious project?

For routine parts often yes, for complex architecture and debugging it may not be. Do not rely on price and index: test the model on three or four of your real tasks.

What happens if the agent loops?

It keeps spending the balance until it hits a limit. So set a daily limit on the key and watch spending in the "Usage" section of the dashboard.