API credits and billing

A thirds.ai credit is the unit you pay with for each finished file. With thirds.ai, you save a design once, such as an invoice, a certificate, or a social post. Then you type in new details and get a finished PDF or image with your logo, colours, and fonts. Each PDF or image costs one credit when it succeeds, whether you export it in the editor, make it from a spreadsheet, or ask for it from your own code. If a file fails or reaches a safety limit, you pay nothing for it. A verified free account gets 50 credits each month, and you don't need a card.

You stop rebuilding the same file by hand, and you pay only for the files you get. Saving a design and editing it by hand cost nothing. You don't need code to use credits. How to make a template you can reuse shows how to make and export your first file in the editor.

What one credit pays for

One thirds.ai credit pays for one finished PDF or image. You pay the same price for PNG, JPEG, WebP, and PDF output. Pages, pixels, JavaScript, quality, and render time don't change the price. There is no bulk discount, so 100 files cost 100 credits.

Adding sizes to a saved image template is free. An image pack or a CSV batch costs one credit per successful file. Each successful carousel slide image costs one credit. A PDF of the selected slides still costs one credit. A size, slide, or row that fails costs nothing. The invoice PDF recipe walks through this exact cost for a retainer client's monthly invoice.

Check the cost before you start

Every paid action in thirds.ai has a fixed credit price, and you see it before you spend anything. A finished file costs 1 credit, AI work costs 25 or 50 credits, and edits by hand cost nothing. Opening a page never spends credits.

The AI build price includes the previews that the AI uses to check its work. Failed internal AI work costs zero. The editor's live layout preview is free. Exported files stay in Renders until they expire or you delete them.

You can check a file's progress and download a finished file again without another charge. Before you retry a create request, read how to retry a request without paying twice. If an agent starts paid work for you, it should show the expected cost and get your instruction first. For a weekly example, see how to make event posters with OpenClaw and approve the credit total before each run. The OpenClaw MCP setup shows how to test one file before you set a schedule. See how to connect your AI agent. To cap what one key can spend on overage, read account and API keys for the request fields.

Check your balance and reserved credits

Your billing page shows your thirds.ai credit balance and your purchases. From your own code, read the credit value that comes back with each file. It tells you whether that file's credit is held, spent, or returned. There is no separate balance request in the API.

When thirds.ai accepts a request, it holds the credits that the work needs. This is a reservation. You can't spend those credits on other work while the request runs. The final result decides whether thirds.ai spends them or returns them to your balance.

For a render, read the job's credit field:

If thirds.ai retries work inside a job, it keeps the same reservation. A request that fails before thirds.ai accepts it creates no job and reserves no credits. Deleting an output after success doesn't return its credit.

Check reserved credits if the balance differs from what you expect from completed jobs. Keep each job ID with your own records so you can check its final result.

Choose how to buy credits

Pick a thirds.ai plan when you make files every month, and a credit pack when your work comes in bursts. Plan credits last three months, and pack credits last 12 months. The 50 free monthly credits can pay for files or AI work. See pricing for plans and credit packs.

Every plan includes the same creation tools and render limits. Plans differ in the number of credits, the number of brand kits, the rows in one CSV batch, and their place in the render queue.

On Free, 50 credits arrive on your signup day each month if your account is verified and in good standing. Unused free credits expire when your next free credits arrive. If your signup day doesn't exist in a shorter month, you get them on the last day of that month. You get them on your usual day again when it returns. You can use free monthly credits for an AI build, image import, AI edit, or AI image.

Paid plans add plan credits and 50 free credits on your billing day each month, even when you pay for a year. A shorter month uses its last day, then your usual billing day returns. The billing page shows when your next credits arrive and when your plan renews. thirds.ai spends credits with the nearest expiry date first.

You can also buy a credit pack with or without a subscription. Each pack is a one-time purchase, and its 12 months start when you pay.

A new account can take one seven-day trial of the Starter plan with a card. The trial costs $1, and thirds.ai doesn't refund the $1. The trial gives you 500 credits that expire when it ends. Extra spending through overage is off during the trial. After seven days the trial becomes Starter at $29 a month or $290 a year. Cancel before the trial ends to avoid the first plan charge. Growth and Scale have no trial. Use the billing portal on your account billing page to manage your plan, payment method, and invoices.

Credits appear after thirds.ai verifies the payment event. A checkout success page alone doesn't confirm that step. If your balance hasn't changed after checkout, refresh the billing page before you buy again. Contact support if the balance stays wrong. For short answers on failed files, running out of credits, and free credits, read the billing questions.

Limit overage spending

You can limit overage on thirds.ai in two ways. Your account has a monthly overage limit equal to one month of your plan's credits, and you can set a lower cap on each API key. Overage lets an active paid subscription keep working after its prepaid credits run out, at $0.015 per credit on every paid plan.

Overage is an amount you owe, so your prepaid credit balance stays at zero or above. A failed file adds no overage charge.

You can't start new overage during a trial, after a failed invoice, or while your subscription can't accept new charges. You can still use prepaid credits if your account otherwise has access.

The per-key cap is called monthly_overage_cap. Both limits follow the UTC calendar month. They count credits held for running work as well as credits already spent.

To set a key's cap, call PATCH /v1/keys/{key_id} with a positive integer monthly_overage_cap in credits. Send null to remove that key's cap. This cap limits overage only. It doesn't limit prepaid credit use or all account spending. The OpenAPI contract gives the request fields.

Recover from a billing refusal

A billing refusal is an error code that tells you why thirds.ai didn't start paid work. The refused request makes no file and holds no credits, and each code below has one next step.

Wait for a balance or billing change before you retry a refused request. The API error codes list shows every other code and the HTTP status it comes with. For a disputed charge, send support the job ID and request ID. Keep card numbers, API keys, and private documents out of that message.