Free AI model API: what you can actually get without paying

A search for "free AI model API" usually means: I want to try models in my code or bot without paying. The honest answer is that nobody offers unlimited free access: every request costs the provider compute. But you can try things almost for free. Below: what actually exists, how to get $0.50 in Zukko, which models are cheapest, and how many requests that covers at October 7, 2026 prices.

Free AI model API: what actually exists

• Trial quotas from providers. Some providers give free limits for getting started. Terms, limits and availability from Russia change — check the specific provider's site.
• Local open models. Tokens are free, but you pay in hardware and electricity, and closed models like Claude and GPT can't be run locally. More in the article local model or API↗.
• "Free keys" from the internet and dubious intermediaries. Other people's keys are usually leaked or stolen, and your requests and data go to who knows where. Not an option for real work.
• Zukko. There's no sign-up bonus. There's a one-time $0.50 for subscribing to the @zukkopro Telegram channel; after that it's pay-per-token with no subscription, top-ups from $1.

How to get $0.50 in Zukko

1. Sign up at zukko.pro.
2. Link your Telegram in the dashboard.
3. Subscribe to the @zukkopro↗ channel.
4. Go back to the dashboard and click "Check" — the bonus is credited to your balance.

The bonus is given once per Telegram account. Details are in the article on the channel subscription bonus↗.

The cheapest models and how many requests $0.50 buys

Take a typical short request: 1,000 input tokens (a question with a bit of context) and 300 output tokens (a one-paragraph answer). Formulas:

Zukko prices in USD per 1M tokens, as of October 7, 2026:

For comparison, the same request on more expensive models (since October 6, Gemini 3.8 Flash is among them too: 0.063 / 0.288, index 41):

Checking one row: DeepSeek V4.1 Flash — 1,000 × 0.013 + 300 × 0.038 = 13 + 11.4 = 24.4, divided by a million: $0.0000244. 0.50 / 0.0000244 ≈ 20,491 requests.

The index in the table is the intelligence index from the Zukko catalog (the Artificial Analysis Intelligence Index, a composite benchmark score); two models have no data. It's a guide, not a guarantee: test a cheap model on your own tasks.

The real number of requests will be lower than calculated if:

• you're running a conversation — each new request carries the whole history;
• answers are longer than 300 tokens;
• requests include images or the model spends tokens on reasoning.

This is an example calculation. Prices change; for the current list and prices, call GET https://api.zukko.pro/v1/models or open the Models page in the dashboard.

How to avoid overspending

Even with a $0.50 bonus it's easy to slip: you forgot to cap the answer, a client defaulted to an expensive model, a script got stuck in a loop. A few settings prevent this.

A separate key with limits

Create a key for experiments and give it daily and monthly dollar limits. Once a limit is reached, requests return 429 with the code key_daily_limit_reached or key_monthly_limit_reached — no money goes beyond the limit. How to set it up is in the key limits docs↗.

Cheap models only

On the same key, set a list of allowed models, for example deepseek-v4.1-flash and glm-5.3-flash. A request to any other model returns 403 model_not_allowed_for_key. This protects you from programs that pick an expensive model by default.

Capping the answer

Pass max_tokens: for most models output costs more than input, and a long answer is a common cause of extra spending.

Short history

Don't drag the whole conversation into every request. Keep the last few messages or a short summary of what came before.

A Python example with these precautions:

import os
from openai import OpenAI, APIStatusError

client = OpenAI(base_url="https://api.zukko.pro/v1", api_key=os.environ["OPENAI_API_KEY"])

try:
    resp = client.chat.completions.create(
        model="deepseek-v4.1-flash",
        max_tokens=300,
        messages=[{"role": "user", "content": "Come up with three names for a coffee shop"}],
    )
    print(resp.choices[0].message.content)
    print("tokens:", resp.usage.prompt_tokens, "+", resp.usage.completion_tokens)
except APIStatusError as e:
    if e.status_code == 429:
        print("Key limit reached or the model provider's rate limit kicked in")
    elif e.status_code == 402:
        print("Insufficient balance")
    else:
        raise

Per-request spending is shown in the dashboard under Usage. Step-by-step setup is in the quick start↗.

When the bonus runs out

Top-ups start at $1: via SBP or a Russian card (Mir, Visa, MasterCard) in rubles at the market rate at the time of payment, via cryptocurrency, or with a foreign card. There's no subscription — you pay only for tokens. For reference: $1 on DeepSeek V4.1 Flash with the same profile is 1 / 0.0000244 ≈ 40,983 requests.

To get started, create a key in the dashboard↗ and set a limit on it right away.

FAQ

Does Zukko have a free plan?

No. There's a one-time $0.50 bonus for subscribing to the @zukkopro Telegram channel; after that you pay for the tokens you actually use.

Can I get the bonus more than once?

No, the bonus is credited once per Telegram account.

Which model is the cheapest?

At October 7, 2026 prices, DeepSeek V4.1 Flash: $0.013 per 1M input and $0.038 per 1M output tokens. Whether its quality works for you — test it on your own examples.

Is the bonus enough to try Claude?

Yes. With a "1,000 input, 300 output tokens" profile, $0.50 covers about 500 requests to Claude Sonnet 5 or 250 requests to Claude Opus 5.5.