How We Built the Yotru Postcard API: Three Calls, and Only One Costs Money

Yotru's API sends personalized postcards from your own software. You make a card, add recipients and approve the campaign. Only that last step costs money. You do not need a design file: the card is built from your website. This post explains why we set it up that way.

Why an API?

We launched it in November 2026. The request came from a customer who wanted to send cards from their own system, without exporting a list and uploading it to us every time.

Plenty of businesses are in the same spot. A CRM knows when someone has been a customer for a year. A store knows who has not ordered in six months. A booking system knows who missed an appointment. With the API, that system queues the postcard itself.

How does it work in three calls?

GET /v1/cards/{id}/preview/front returns the image exactly as it will be printed. Every card gets its own QR code, the same as an order placed on the site. The full reference is in the API documentation.

What do you get back?

You see which recipient scanned the QR code on their card. It shows in your dashboard, and you can get a notification by email or Slack the moment it happens. A card your software queues on Tuesday can turn into a phone call on Friday with someone who has just read it.

Free to build, pay when you approve

Making a card, fetching a preview and adding recipients costs nothing. You pay when you approve a campaign. So you can build and try the whole integration before you spend a cent.

There is no separate sandbox to set up. From the first call you work with the real result: the preview you fetch is the same image that goes to the printer.

What happens to an address that is wrong?

That one address is refused and the rest go through. Each recipient comes back as accepted with an id, or as refused with a reason, such as address or duplicate. Your system knows what went wrong on each row and does not have to resend the whole list.

If you send the same call twice by accident, an Idempotency-Key header keeps people from landing on the list twice.

What does it cost?

The same as an order placed on the site. There is no minimum: you pay for the cards on the campaign. Below 100 cards, each one costs the per-card price for 100. Prices are on the pricing page.

What is good to know before you build?

• A person checks every batch before it prints. After you approve, someone on our side looks at the batch before it goes to the printer. A mistake on a thousand printed cards cannot be taken back.
• You build with ten templates. You fill them with your own text, colors, logo and photo.
• Status is one call away. A campaign is open, awaiting payment, approved, printing or sent.

How do you start?

Make an account and open Settings, then API. Your first key is made when you open that page, and it is shown once. You have to be an owner or admin of the account, with a confirmed email address. Then follow the four steps in the API documentation.

Frequently asked questions

Can you test the API for free?

Yes. Making cards and adding recipients costs nothing. You only pay when you approve a campaign.

How many recipients can you send at once?

Up to 1,000 per call. Each key is limited to 120 calls a minute.

Is there a minimum number of cards?

No. Below 100 cards you pay the per-card price that goes with 100.