Playground
The Playground runs every model from the browser. Each model has recorded examples that open instantly, and an upload field that runs real inference on a chosen image. Results show timing, cost, the raw JSON and a “copy as code” snippet in curl and Python, with the key written as the placeholder $FOLDBUN_API_KEY.
The Playground is a separate web client with its own endpoints, which are not part of the public API. Integrations call /v1 with an API key. See Quickstart.
Trial lane
Section titled “Trial lane”The trial lane is for anyone, without an account. It serves all seven models.
- Anonymous. No sign-in and no key.
- Automatic human check. Each submission passes an automatic human check (Cloudflare Turnstile). The check can be invisible or interactive.
- Lowest priority. Trial jobs are queued behind API traffic and are refused first when a model is busy. Only one trial job per model runs at a time; the Playground shows how many trial requests are ahead and the time spent waiting.
- Not charged. Trial calls cost nothing. The response shows
costas 0 and the list price in credits the call would have been worth. - Capacity is limited. When the queue of a model is full or the daily trial budget is spent, the call is refused with
503 trial_busy, which is retryable.
One check, several calls
Section titled “One check, several calls”Some demos need more than one API call per submission. After one successful human check, a short-lived trial grant covers the follow-up calls of that submission, so no new check is needed.
| Model | One grant covers (within 10 minutes) |
|---|---|
sam3, sam-lite |
Up to 10 segment calls and 100 refine calls, on the image of the first call |
dinov3 |
Up to 4 image calls |
siglip2 |
Up to 2 calls: one image and one set of texts |
ppocr-v6, paddleocr-vl, birefnet |
1 call |
An expired or used-up grant is refused with 403 trial_grant_invalid, and the Playground asks for a new check.
Trial input limits
Section titled “Trial input limits”- Images are sent as base64, at most 8 MiB after decoding. For SAM follow-up calls, the
img_handle of the grant’s image is also accepted. sam3: at most 5 text prompts and 10 prompts in total per call.siglip2: at most 16 texts per call.- Trial calls are limited per IP address to 20 calls per minute, with a burst of 10. This only stops scripts.
- Images of the trial lane are deleted after 1 hour.
Signed-in lane
Section titled “Signed-in lane”A signed-in account with a verified email can run the Playground on its own credit. The rules are the same as for /v1: pools, limits, billing, idempotency. Usage appears in the console as “Playground”. No API key is needed, and no key exists in the browser.