black-forest-labs/flux-2-klein-9b-lora/text-to-imageAb 3 Credits pro Bild· Bild erstellenFLUX.2 Klein 9B LoRA betreibt das schrittdestillierte FLUX.2 [klein] 9B von Black Forest Labs mit bis zu drei Ihrer eigenen LoRA-Dateien pro Anfrage. Text-zu-Bild gibt es in neun Seitenverhältnissen mit 1k oder 2k, die Bearbeitung nimmt ein bis drei Referenzbilder. Die meisten unserer Testbilder kamen nach etwa zehn Sekunden zurück, zu einem Festpreis pro Bild und ohne Prüfung von Prompts, Gewichten oder Ergebnissen.
Du rufst es mit dem Modellnamen black-forest-labs/flux-2-klein-9b-lora/text-to-image über POST /jobs/createTask auf, ab 3 Credits pro Bild (0,03 $). Neue Konten bekommen 30 kostenlose Credits, damit du es zuerst im Playground testen kannst.
- Bild erstellen
- Bild bearbeiten
- Bis 2K
- Bis zu 3 Referenzbilder
- 9 Seitenverhältnisse
- Lädt eigene LoRAs
black-forest-labs/flux-2-klein-9b-lora/text-to-imagePOST https://api.popnow.ai/api/v1/jobs/createTask# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(uuidgen)"
curl -X POST https://api.popnow.ai/api/v1/jobs/createTask \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-H "Idempotency-Key: $IDEMPOTENCY_KEY" \
-d '{
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "1:1",
"resolution": "1k"
}
}'
# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $POPNOW_API_KEY"// Node 18+ (or any runtime with fetch). Keep the API key on your server.
const BASE = "https://api.popnow.ai/api/v1";
const headers = { Authorization: `Bearer ${process.env.POPNOW_API_KEY}` };
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));
async function call(path, init = {}) {
const res = await fetch(BASE + path, { ...init, headers: { ...headers, ...init.headers } });
const body = await res.json();
if (body.code !== 200) throw new Error(`${body.code} ${body.msg}`);
return body.data;
}
const { taskId } = await call("/jobs/createTask", {
method: "POST",
headers: { "Content-Type": "application/json", "Idempotency-Key": crypto.randomUUID() },
body: JSON.stringify({
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "1:1",
"resolution": "1k"
}
}),
});
// Poll with backoff. A finished task may still be copying files: wait while an asset is pending.
let task;
for (let delay = 2000; ; delay = Math.min(delay * 1.5, 15000)) {
await sleep(delay);
task = await call(`/jobs/recordInfo?taskId=${taskId}`);
const copying = (task.output?.assets ?? []).some((a) => a.pending && !a.unavailable);
if (["succeeded", "failed", "canceled", "expired"].includes(task.state) && !copying) break;
}
if (task.state !== "succeeded") throw new Error(`${task.state}: ${task.errorMessage ?? "no detail"}`);
// Each asset has a signed url (no API key needed) that expires at expiresAt: save the file.
for (const asset of task.output.assets) console.log(asset.url);import os, time, uuid, requests
BASE = "https://api.popnow.ai/api/v1"
HEADERS = {"Authorization": f"Bearer {os.environ['POPNOW_API_KEY']}"}
def call(method, path, **kwargs):
body = requests.request(method, BASE + path, headers={**HEADERS, **kwargs.pop("headers", {})}, timeout=30, **kwargs).json()
if body["code"] != 200:
raise RuntimeError(f'{body["code"]} {body["msg"]}')
return body["data"]
task_id = call(
"POST",
"/jobs/createTask",
headers={"Idempotency-Key": str(uuid.uuid4())}, # reuse it if you retry
json={
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "1:1",
"resolution": "1k"
}
},
)["taskId"]
# Poll with backoff. A finished task may still be copying files: wait while an asset is pending.
delay = 2.0
while True:
time.sleep(delay)
task = call("GET", "/jobs/recordInfo", params={"taskId": task_id})
assets = (task.get("output") or {}).get("assets") or []
copying = any(a.get("pending") and not a.get("unavailable") for a in assets)
if task["state"] in ("succeeded", "failed", "canceled", "expired") and not copying:
break
delay = min(delay * 1.5, 15.0)
if task["state"] != "succeeded":
raise RuntimeError(f'{task["state"]}: {task.get("errorMessage", "no detail")}')
# Each asset has a signed url (no API key needed) that expires at expiresAt: save the file.
for asset in assets:
print(asset["url"])Der input ist aus dem Schema unten gebaut und besteht die Prüfung so, wie er dasteht. Ersetz Prompt und Links durch deine eigenen.
Preis
| Option | Credits pro Bild | ≈ USD |
|---|---|---|
| Standard | 2,7 | 0,027 $ |
1 Credit = 0,01 $ · Alle Optionen und Preise: GET /models/black-forest-labs/flux-2-klein-9b-lora/text-to-image
Jede Aufgabe wird auf ganze Credits aufgerundet, ein Lauf in der günstigsten Stufe kostet also 3 Credits pro Bild (0,03 $).
Limits
- Auflösungen
- 1K · 2K
- Seitenverhältnisse
- 1:1 · 16:9 · 9:16 · 4:3 · 3:4 · 3:2 +3
- Prompt-Länge (Zeichen)
- 5,000
Parameter
Diese Felder stammen aus demselben Schema, gegen das wir jede Anfrage prüfen. Nicht aufgeführte Felder werden abgelehnt.
promptstringPflichtDescribe the subject, setting, light and style in plain sentences. Put a LoRA trigger phrase first.
aspect_ratiostringOptionalDie Form des Bildes: breit, quadratisch oder hoch.
resolutionstringOptionalAusgabegröße. Größere Formate sind schärfer und kosten mehr.
lorasarray<object>OptionalLade eigene LoRA-Dateien, um einen Stil oder eine Figur festzulegen.
Felder darin
loras[].pathstringPflichtDirect URL of a LoRA weights file.
loras[].scalenumberPflichtWeight strength from zero to four.
seedintegerOptionalDieselbe Zahl liefert ein wiederholbares Ergebnis.
Rohes JSON-Schema
{
"additionalProperties": false,
"properties": {
"aspect_ratio": {
"default": "1:1",
"description": "Output aspect ratio.",
"enum": [
"1:1",
"16:9",
"9:16",
"4:3",
"3:4",
"3:2",
"2:3",
"21:9",
"9:21"
],
"type": "string"
},
"loras": {
"default": [],
"description": "Up to three LoRA weight files trained for FLUX.2 [klein] 9B (the distilled or the Base build), each with its own strength.",
"items": {
"additionalProperties": false,
"properties": {
"path": {
"contentMediaType": [
"application/octet-stream"
],
"description": "Direct URL of a LoRA weights file.",
"format": "uri",
"minLength": 1,
"type": "string"
},
"scale": {
"default": 1,
"description": "Weight strength from zero to four.",
"maximum": 4,
"minimum": 0,
"type": "number"
}
},
"required": [
"path",
"scale"
],
"type": "object"
},
"maxItems": 3,
"type": "array"
},
"prompt": {
"description": "Describe the subject, setting, light and style in plain sentences. Put a LoRA trigger phrase first.",
"maxLength": 5000,
"minLength": 1,
"type": "string"
},
"resolution": {
"default": "1k",
"description": "Output size tier: 1k is about one megapixel, 2k is 2048 pixels on the long side.",
"enum": [
"1k",
"2k"
],
"type": "string"
},
"seed": {
"description": "Random seed for controlled comparisons.",
"maximum": 2147483647,
"minimum": 0,
"type": "integer"
}
},
"required": [
"prompt"
],
"type": "object"
}Ein echtes Ergebnis von FLUX.2 Klein 9B LoRA

AnalogRedmAF, Analog. Looking up a raw concrete spiral stairwell, one hard shaft of daylight falling from a skylight. A man in his late thirties with dark brown skin and a close-cropped beard leans on the curved concrete balustrade in a cream linen shirt open at the collar, sleeves rolled to the elbow, looking down into the lens with a slow, confident half-smile. 35mm film photograph, warm grain, soft halation, deep shadows.
{
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"input": {
"prompt": "AnalogRedmAF, Analog. Looking up a raw concrete spiral stairwell, one hard shaft of daylight falling from a skylight. A man in his late thirties with dark brown skin and a close-cropped beard leans on the curved concrete balustrade in a cream linen shirt open at the collar, sleeves rolled to the elbow, looking down into the lens with a slow, confident half-smile. 35mm film photograph, warm grain, soft halation, deep shadows.",
"aspect_ratio": "2:3",
"resolution": "1k",
"seed": 101
}
}Antworten, Polling und Callbacks
Alle Modelle funktionieren gleich: Task anlegen, dann pollen oder auf den Callback warten.
Erst den Preis prüfen
curl -X POST https://api.popnow.ai/api/v1/jobs/quote \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "1:1",
"resolution": "1k"
}
}'Gleicher Body wie bei createTask. Liefert die erwartete und die höchstmögliche Abbuchung und startet nichts.
Angenommen
HTTP/1.1 202 Accepted
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"state": "queued"
},
"request_id": "req_example_create"
}HTTP 202 heißt: Der Task ist angenommen, die Credits sind reserviert, aber noch nicht abgebucht. Die endgültige Abbuchung liegt nie über der Reservierung.
Status abfragen
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $POPNOW_API_KEY"Frag alle paar Sekunden mit wachsendem Abstand ab und hör auf, sobald state succeeded, failed, canceled oder expired ist.
Fertiger Task
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"model": "black-forest-labs/flux-2-klein-9b-lora/text-to-image",
"state": "succeeded",
"output": {
"assets": [
{
"url": "https://cdn.popnow.ai/tasks/task_01k3m8x9q2z4v7n5p6r8s0t1w3/output.png?signature=FROM_RESPONSE",
"expiresAt": "2026-10-17T12:20:00Z",
"mime": "image/png",
"width": 1024,
"height": 1024
}
]
},
"settled": true
},
"request_id": "req_example_record"
}Lad über die url vor expiresAt herunter. Später einen frischen Link nötig? Frag POST /common/download-url.
Callback prüfen
import { createHash, createHmac, timingSafeEqual } from "node:crypto";
import express from "express";
const app = express();
// express.raw keeps the exact bytes that were signed; express.json would not match.
app.post("/hooks/popnow", express.raw({ type: "application/json" }), (req, res) => {
const timestamp = req.header("X-Webhook-Timestamp");
const signature = req.header("X-Webhook-Signature") ?? "";
const body = JSON.parse(req.body.toString("utf8"));
const taskId = body.data?.taskId ?? body.task_id;
const digest = createHash("sha256").update(req.body).digest("hex");
const expected = createHmac("sha256", process.env.POPNOW_WEBHOOK_SECRET)
.update(`${taskId}.${timestamp}.${digest}`)
.digest("base64");
const ok = expected.length === signature.length && timingSafeEqual(Buffer.from(expected), Buffer.from(signature));
// Check the signature first, then reject anything older than five minutes.
if (!ok || Math.abs(Date.now() / 1000 - Number(timestamp)) > 300) return res.status(401).end();
res.status(200).end(); // answer fast, then fetch the task and store its files
});Mit gesetzter callBackUrl schicken wir dir den fertigen Task. Prüf die Signatur am rohen Body, bevor du ihm vertraust.
Lokale Datei schicken
curl -X POST https://api.popnow.ai/api/v1/common/upload-url \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-d '{"contentType": "image/png", "bytes": 482113}'
# PUT the file bytes to data.uploadUrl with every header in data.headers, then commit it:
curl -X POST https://api.popnow.ai/api/v1/files/$FILE_ID/commit \
-H "Authorization: Bearer $POPNOW_API_KEY"
# The commit returns a popnow://f/... reference. Put it in any image, video or
# audio field of the task input instead of a public https URL.Öffentliche https-Links funktionieren direkt. Lokale Dateien laufen vorher über upload-url und commit.

