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API Key Guide

Setting up your own API key for cloud AI generation (Kuku Pro)

Cloud AI generation in Kuku uses your own API key (a BYO-key model) to talk directly to the AI provider you choose. Nothing goes through the developer's servers, so there is no extra service fee — but you sign up with each provider yourself (creating an API key, and paying them if needed). This page covers how to get a key from each of the four providers, their free tiers, and what to watch out for.

Specs and prices below are based on research as of July 2026. Always check each provider's official pages for the latest terms.

1. The four providers at a glance

Claude (Anthropic)Gemini (Google)GPT (OpenAI)Qwen (Alibaba Cloud)
Free to try?Yes — $5 starter credit (no card required, expires)Partly — there is a permanent free tier, but Kuku's web-search generation does not work on itNo — effectively none (a $5 purchase is required to start)Yes — 1 million tokens per model for 90 days (but generation runs without web search on the free tier)
Card requiredNot for the free trialYes for practical use (billing must be enabled)YesA payment method must be registered (PayPal accepted, no prepayment)
Free tier trains on your dataNo (same treatment as paid)Yes (stops once billing is enabled)No by default (the "free daily tokens" offer requires opting in to sharing)No (stated explicitly in the official FAQ)
Cost per generationAbout $0.10–0.15About $0.05 (cheapest)About $0.10–0.18$0 within the free tier / about $0.01–0.03 after
Cost for 30–50 / monthAbout $3–7About $1.5–3About $4–9$0 within the free tier / about $0.5–1.5 after
Key formatsk-ant-…AQ.…sk-proj-…sk-ws-…

Not sure? Start with the Claude free credit. If you want to keep going, either top up Claude, or switch to Gemini (with billing enabled) for the lowest running cost. If free-tier size matters most, Qwen is also an option (though generation runs without web search on its free tier).

2. Free tiers may use your data for training

⚠ On free tiers, what you send may be used by the AI provider for training and product improvement. Your goals and how you break them down can be personal information. If this matters to you, choose a provider and plan that guarantees no training on your data.

3. Claude (Anthropic) — best way to try for free

The starter credit — no card required — lets you try Kuku's full web-search generation as intended. Your prompts are not used for training even while on the free credit.

How to get a key (entirely from your phone's browser)

  1. Create an account at console.anthropic.com (email, or a Google / GitHub account). This is a separate service from the claude.ai chat app — a Claude Pro / Max subscription does not include the API; you set it up separately in this Console.
  2. Verify your phone number via SMS.
  3. When the starter credit ($5) offer appears, claim it. It can expire about 14 days after claiming, so claim it when you are ready to try.
  4. Go to Settings → API keys (console.anthropic.com/settings/keys), tap Create API Key, give it a name, and create it.
  5. Copy the key (sk-ant-…) right away — it is shown only once, at creation. → Adding it to Kuku

When the free credit runs out

4. Gemini (Google) — cheapest for ongoing use

With a Google account, you can create a key in a few clicks. For practical use with Kuku, though, there are two caveats: (a) on the free tier, your input is used for training (see §2 above), and (b) the Google Search grounding that Kuku's generation needs is not available on the free tier — so enabling billing is effectively required. Once billing is on, training use stops, and the running cost is the lowest of the three (about $0.05 per generation).

How to get a key

  1. Open aistudio.google.com/apikey and sign in with your Google account.
  2. Accept the terms and tap Create API key to get a key (AQ.…). No card required at this point.
  3. For practical use with Kuku, set up billing from the same page (link a Cloud Billing account; card required). It is pay-as-you-go with no prepayment, and search grounding is included at no extra cost up to 5,000 requests per month.
  4. Copy the key. → Adding it to Kuku

Cost estimate: about $0.05 per Kuku generation. Even 30–60 generations a month only comes to a few dollars.

5. GPT (OpenAI)

There is effectively no way to try it for free (the new-account credit has been discontinued); you need to register a card and prepay $5 to start. It suits people who already have credit with OpenAI or who prefer GPT's output. A ChatGPT Plus subscription does not include the API — it is billed separately.

How to get a key

  1. Create an account at platform.openai.com, then complete email confirmation and SMS verification.
  2. Under Billing, add a payment method and buy credit (minimum $5, prepaid). Without this, the key will not work even once created.
  3. Go to API keys (platform.openai.com/api-keys) and run Create new secret key.
  4. Copy the key (sk-proj-…) right away (it is shown only once). → Adding it to Kuku

Cost estimate: about $0.10–0.18 per Kuku generation (web search included). If you see the "free daily tokens in exchange for data sharing" offer, remember the caveat in §2.

6. Qwen (Alibaba Cloud) — the biggest free tier

Qwen is the model family on Alibaba Cloud's international AI platform, Model Studio. It offers a generous free tier — 1 million tokens per model, valid for 90 days — with no prepaid top-up needed, and your input is never used for training (stated in the official FAQ). Two caveats: (a) issuing a key requires registering a payment method (PayPal accepted; registering alone does not charge you), and (b) web search is not covered by the free tier (about $0.01 per search), so on a free-tier-only key, generation runs without web search.

How to get a key

  1. Create an account at alibabacloud.com (email sign-up).
  2. Open the Model Studio console, accept the terms, and activate the service. Choose the Singapore region (the free tier is Singapore-only).
  3. If you are asked to complete your account information when creating a key, finish it. This step requires registering a payment method (card or PayPal). Registering alone does not charge you.
  4. On the API-Key page, run Create API Key and copy the key (sk-ws-…) right away (it is shown only once; you can Reset to reissue if lost). → Adding it to Kuku
  5. Recommended: under Usage and Billing → Free Quota, batch-enable Stop-on-Exhaust — when the free quota runs out, the service simply stops instead of charging you (no surprise bills).

Cost estimate: $0 within the free tier. Even after it runs out, about $0.01–0.03 per generation — the lowest of the four (add $0.01 per generation if using web search).

7. Adding the key to Kuku (just copy and paste)

Kuku's new chart screen — AI generation options
  1. Copy the key on the provider's page. If you got it on a Mac / PC, you can paste it directly on an iPhone signed in to the same Apple ID (Universal Clipboard). Avoid passing it through email or notes.
  2. Open Kuku and go to the gear icon at the top right of Home → Settings.
  3. Tap the paste button next to that provider's key field, then save (no permission dialog needed; long-press → Paste also works). The key is displayed masked and stored only in your device's Keychain (it is never sent to the developer's servers).
  4. The "provider used for generation" is set automatically to the provider whose key you added. If you add several, you can switch between them here.
  5. On the new chart screen, choose "Cloud AI" and you are ready (Kuku Pro required).

When you paste, leading/trailing spaces and line breaks are removed automatically, and a warning appears before saving if the key belongs to a different provider. If you still see the "Invalid API key" error, clear the field and save (which deletes the key), then paste it again.

8. Keeping your key safe

For how to use the app, see the User Guide. Questions? Reach us at support@kiribako.app.