An OpenAI API key lets apps like Cinematic Recorder use OpenAI's models on your behalf, with usage billed to your own account. Getting one takes a few minutes, but there are two things beginners often skip: setting a spending limit and keeping the key private. This guide walks through creating your OpenAI API key, protecting your budget and adding it to the app.
What an API key is (and isn't)
An API key is a long secret code that identifies your account when an app talks to OpenAI. It is not the same as a ChatGPT subscription. A ChatGPT plan pays for the chat app; the API is billed separately, usually as prepaid credit that is used up as you make requests.
Think of the key like a card PIN for your AI credit. Anyone who has it can spend your credit, so you never post it in a group, a screenshot or a video. If you want the bigger picture first, read our guide on why Cinematic Recorder uses your own AI key.
Step 1: Create your OpenAI API account
- Open platform.openai.com in a browser. A laptop is easier, but a phone browser works.
- Sign up or log in. You can use an email address or an existing Google or Microsoft account.
- If asked, create an organisation or project. A simple name like "Video editing" is fine.
- You may need to verify a phone number.
Step 2: Add credit and set a spending limit
Most new accounts need some credit before the API will answer requests. In the dashboard, look for Settings and then Billing. Add a small amount of credit to start. A small top-up is plenty for testing; you can always add more later.
Then look for Limits (sometimes called usage limits or budgets). Here you can usually set a monthly budget and an email alert when you reach part of it. Set a number you are comfortable losing completely, because that's the worst case if something goes wrong.
For more ways to keep the bill small, see how to keep AI costs low with your own key.
Step 3: Create the OpenAI API key
- In the dashboard, open the API keys page (usually in the left menu or under your project settings).
- Tap Create new secret key.
- Give it a clear name, such as "Cinematic Recorder – my phone". Naming each key by device makes it easy to cancel one later.
- If there is a permissions option, the default is fine for most people. Advanced users can restrict it.
- Copy the key immediately. OpenAI usually shows the full key only once. If you lose it, just create a new one.
Step 4: Add the key to Cinematic Recorder
- Open Cinematic Recorder on your Android phone.
- Go to the AI or "bring your own key" settings.
- Choose OpenAI as the provider.
- Paste the key and save. If the app offers a model choice, start with a smaller, cheaper model for text tasks.
The key is stored in Android Keystore, the phone's protected storage for secrets, and is never sent to our servers. When an AI feature runs, your phone talks directly to OpenAI with your key. You can read more on the features page.
A quick honest note: your OpenAI key is used today for captions written from your speech and for cutting the silent pauses. The full AI editing assistant and AI translation are still coming soon, and the rest of the editor works without any key.
Keeping your key safe over time
Use one key per device or app
If your phone is lost, you can delete just that key in the OpenAI dashboard without breaking anything else.
Check usage once in a while
The usage page shows how much you spent and when. If you see activity you don't recognise, delete the key at once and create a new one.
Rotate keys occasionally
Every few months, create a new key, put it in the app and delete the old one. It takes a minute and limits damage from any old leak.
Remove it when you stop
If you stop using AI, remove the key from the app and delete it in the dashboard. You can also simply use the editor with AI turned off.
Troubleshooting common problems
| Problem | Likely cause | What to try |
|---|---|---|
| "Invalid key" | Extra space or a missing character when pasting | Copy the key again carefully, or create a new one |
| "Quota exceeded" or billing error | No credit, or the limit was reached | Check Billing and Limits in the dashboard |
| Model not available | Your account doesn't have access to that model | Choose a different model in the app |
| Very slow replies | Weak internet or a large model | Switch to Wi-Fi or a smaller model |
FAQ
Is an OpenAI API key free?
Creating the key is free, but using the API usually costs money based on how much text or media you process. Check OpenAI's own pricing page for current rates.
Can I use my ChatGPT Plus subscription instead?
No. ChatGPT subscriptions and API usage are billed separately. Apps that use an API key draw from your API credit, not your chat plan.
Does Cinematic Recorder see or store my key on its servers?
No. The key stays in Android Keystore on your phone and is never sent to our servers.
What if I already shared my key by mistake?
Delete it in the OpenAI dashboard right away and create a new one. A deleted key stops working immediately.
Once your key is set up with a sensible limit, you can try other providers too. Compare with a Gemini API key and pick what suits your budget and comfort.
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