Verified before delivery
Every code is decoded and compared to the payload you sent. A code that would not scan comes back as an error, not as an image you find out about from a customer.
QR code API
Branded QR codes, verified to scan
Generate styled, logo-bearing QR codes through one API call. Every code is decoded and checked against your payload before it leaves Renderwolf, so a code that would not scan comes back as an error instead of reaching your customer.
Start generating freeView the QR API docs
- Free on every plan
- Scan verified before delivery
- No card required
- UK-operated infrastructure
dots
dark
mode
logo
{
"data": "https://ironfang.uk/renderwolf",
"dots": "circle", "ecc": "H",
"dark": "#05050a", "light": "#ffffff",
"logo": "data:image/png;base64,..."
}
Scan verified
The problem
A QR code either scans or it is landfill
Most QR libraries hand back an image and wish you luck. Add a logo, tint the modules to match a brand, or style the finder patterns, and the symbol quietly stops decoding. You find out when the codes are already printed, or when a customer cannot check in.
Renderwolf decodes every finished code and compares it to the data you sent. If it does not read back, you get a 422 and no charge, which is a problem you can handle in code rather than in a reprint.
POST /renderwolf/v1/qr
Authorization: Bearer rw_live_...
{
"data": "https://ironfang.uk/renderwolf",
"dots": "circle",
"eyes": "rounded",
"dark": "#4f46e5",
"light": "transparent",
"logo_url": "https://example.com/mark.png",
"size": 512
}Capabilities
Everything the symbol needs, nothing it cannot survive
Style, brand and size the code however the design asks, with the structural guarantees that keep it readable.
Branded without breaking
Drop a logo in the centre and error correction is raised to compensate automatically. Finder patterns always render solid, because styled finders are how QR generators produce codes that do not scan.
Styled to match your product
Square or circular modules, square or rounded eyes, any foreground and background colour, and a transparent ground when you need the code to sit on your own surface.
Inside your templates
Send a qr object with a stored template render and the code becomes a variable in the layout, so invoices, tickets and certificates carry their code natively.
Free on every plan
QR generation costs no credits, on the free plan and every paid one. Requests stay metered so you can see volume, and are never refused when you hit a cap.
One API, one key
The same key and quota that render your screenshots, PDFs and images. No second vendor, no second invoice, no second integration to maintain.
Use cases
Where a verified code earns its place
Anywhere the code is printed, posted or handed to somebody who only gets one attempt at scanning it.
Invoices and statements
Composite a payment or verification code straight into the PDF your application already generates.
Tickets and passes
Generate a unique code per booking at request time, verified to scan before it reaches the customer.
Packaging and print
Print runs are expensive to repeat. A code checked before delivery is a code you can send to the printer.
Asset and equipment labels
Branded codes at any size, with the quiet zone and error correction that survive a label on a scuffed machine.
Campaign and menu codes
Match the code to the design rather than dropping a black square into it, without giving up scannability.
WiFi and device onboarding
Any payload up to a kilobyte, so network credentials and deep links work the same way a URL does.
Pricing
QR codes cost nothing on any plan
Every plan generates QR codes free, including the free one. Requests stay metered per kind so you can see your volume, and they are never refused when you reach a cap. Start with 250 free credits each month for the screenshots, PDFs and images alongside them, with no card required.
Questions
Before you integrate
The details that decide whether this fits, without reading the whole reference first.
Do QR codes use credits?
No. QR generation costs nothing on every plan, including the free one. Requests are still metered per kind so you can see the volume, and they are never refused when you reach a cap.
What happens if a code would not scan?
You get a 422 rather than a broken image. Every code is decoded and compared to your payload before it leaves the API, so an unreadable result is returned as an error instead of shipped to your customer.
Can I put a logo in the middle?
Yes, inline as a data URI or by URL. Error correction is raised to the highest level automatically, and the logo sits on a knockout tile so it covers clean ground. Remote logos face the same target guard and rate caps as a render URL.
Can I generate light modules on a dark background?
Yes, with the invert flag, and the result is verified against the negative so the guarantee still holds. Modern phone cameras read inverted codes and many embedded or in-app scanners do not, so it suits screens rather than print or payments.
Can I put a QR code inside a generated image or PDF?
Yes. Send a qr object with a stored template render and each entry becomes a variable holding a data URI, so the code is composited into the layout rather than fetched separately.
What sizes and formats come back?
A square PNG between 64 and 2048 pixels, with a quiet zone you control from 0 to 8 modules. Identical requests hit the cache, and cache hits are free.
Generate your first verified QR code
Create an account, take a key and send one request. QR codes cost nothing on every plan.
250 free credits each month for everything else, with no card required and hard usage caps.