google/nano-banana-2.1/text-to-imageFrom 8 credits per image· Create ImageNano Banana 2.1 is Google's update to Nano Banana 2 (Gemini 3.1 Flash Image), released on 6 October 2026. Google improved visual quality, prompt adherence, character consistency across edits and text rendering, and says it fixed the tiling seams on wide banners at 2K and 4K. It renders at 1K, 2K or 4K in fourteen shapes up to 8:1, edits with up to fourteen reference images and can search the web or reference pictures first.
Call it with the model name google/nano-banana-2.1/text-to-image on POST /jobs/createTask, from 8 credits per image ($0.08). New accounts get 30 free credits to try it in the Playground first.
- Create Image
- Edit Image
- Up to 4K
- Up to 14 reference images
- 14 aspect ratios
google/nano-banana-2.1/text-to-imagePOST https://api.popnow.ai/api/v1/jobs/createTask# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(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: $IDEMPOTENCY_KEY" \
-d '{
"model": "google/nano-banana-2.1/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "16:9",
"resolution": "1k",
"output_format": "png"
}
}'
# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$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} ${body.msg}`);
return body.data;
}
const { taskId } = await call("/jobs/createTask", {
method: "POST",
headers: { "Content-Type": "application/json", "Idempotency-Key": crypto.randomUUID() },
body: JSON.stringify({
"model": "google/nano-banana-2.1/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "16:9",
"resolution": "1k",
"output_format": "png"
}
}),
});
// Poll with backoff. A finished task may still be copying files: wait while an asset is pending.
let task;
for (let delay = 2000; ; delay = Math.min(delay * 1.5, 15000)) {
await sleep(delay);
task = await call(`/jobs/recordInfo?taskId=${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": "google/nano-banana-2.1/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "16:9",
"resolution": "1k",
"output_format": "png"
}
},
)["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"])The input is built from the schema below, so it passes validation as written. Change the prompt and links to your own.
Price
| Option | Credits per image | ≈ USD |
|---|---|---|
resolution 1K | 7.2 | $0.072 |
resolution 2K | 10.8 | $0.11 |
resolution 4K | 24.3 | $0.24 |
1 credit = $0.01 · Every option and its price: GET /models/google/nano-banana-2.1/text-to-image
Each task is rounded up to whole credits, so one run at the lowest tier costs 8 credits per image ($0.08).
Limits
- Resolutions
- 1K · 2K · 4K
- Aspect ratios
- 1:1 · 3:2 · 2:3 · 3:4 · 4:3 · 4:5 +8
- Prompt length (characters)
- 5,000
Parameters
These fields come from the same schema we check every request against. Fields that are not listed are rejected.
promptstringRequiredDescribe the image you want.
aspect_ratiostringOptionalThe shape of the frame: wide, square or tall.
resolutionstringOptionalChanges the priceOutput size. Bigger sizes look sharper and cost more.
enable_web_searchbooleanOptionalChanges the priceChecks the web first, for dates, places and current facts.
enable_image_searchbooleanOptionalChanges the priceLooks up real pictures of a place or product first.
output_formatstringOptionalFile type of the result.
Raw JSON Schema
{
"type": "object",
"required": [
"prompt"
],
"properties": {
"prompt": {
"type": "string",
"maxLength": 5000,
"minLength": 1,
"description": "Describe the image you want."
},
"resolution": {
"enum": [
"1k",
"2k",
"4k"
],
"type": "string",
"default": "1k",
"description": "Output size tier."
},
"aspect_ratio": {
"enum": [
"1:1",
"3:2",
"2:3",
"3:4",
"4:3",
"4:5",
"5:4",
"9:16",
"16:9",
"21:9",
"1:4",
"4:1",
"1:8",
"8:1"
],
"type": "string",
"default": "16:9",
"description": "Output aspect ratio."
},
"output_format": {
"enum": [
"png",
"jpeg"
],
"type": "string",
"default": "png",
"description": "File format of the result."
},
"enable_web_search": {
"type": "boolean",
"default": false,
"description": "Look up current facts on the web before drawing."
},
"enable_image_search": {
"type": "boolean",
"default": false,
"description": "Look up reference pictures on the web before drawing."
}
},
"additionalProperties": false
}A real result from Nano Banana 2.1

Fashion editorial photograph in a sunlit Andalusian plaza with whitewashed walls: a Spanish woman in her forties with slicked-back dark hair wears a structured tangerine bolero jacket and wide cobalt trousers, and a huge cape made of iridescent soap-bubble film billows behind her like a sail, catching rainbow light. Hard sun, deep shadows, low angle, 35mm film grain, photorealistic, no text.
{
"model": "google/nano-banana-2.1/text-to-image",
"input": {
"prompt": "Fashion editorial photograph in a sunlit Andalusian plaza with whitewashed walls: a Spanish woman in her forties with slicked-back dark hair wears a structured tangerine bolero jacket and wide cobalt trousers, and a huge cape made of iridescent soap-bubble film billows behind her like a sail, catching rainbow light. Hard sun, deep shadows, low angle, 35mm film grain, photorealistic, no text.",
"aspect_ratio": "16:9",
"resolution": "1k",
"output_format": "png"
}
}Responses, polling and callbacks
Every model works the same way: create a task, then poll it or wait for a callback.
Price it first
curl -X POST https://api.popnow.ai/api/v1/jobs/quote \
-H "Authorization: Bearer $POPNOW_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "google/nano-banana-2.1/text-to-image",
"input": {
"prompt": "A ceramic teapot on a linen cloth, soft window light, muted palette",
"aspect_ratio": "16:9",
"resolution": "1k",
"output_format": "png"
}
}'Same body as createTask. It returns the expected and the highest possible charge, and runs nothing.
Accepted
HTTP/1.1 202 Accepted
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"state": "queued"
},
"request_id": "req_example_create"
}HTTP 202 means the task was accepted and the credits are held, not charged yet. The final charge never goes above the hold.
Check status
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
-H "Authorization: Bearer $POPNOW_API_KEY"Poll every few seconds with backoff and stop once state is succeeded, failed, canceled or expired.
Finished task
{
"code": 200,
"msg": "success",
"data": {
"taskId": "task_01k3m8x9q2z4v7n5p6r8s0t1w3",
"model": "google/nano-banana-2.1/text-to-image",
"state": "succeeded",
"output": {
"assets": [
{
"url": "https://cdn.popnow.ai/tasks/task_01k3m8x9q2z4v7n5p6r8s0t1w3/output.png?signature=FROM_RESPONSE",
"expiresAt": "2026-10-17T12:20:00Z",
"mime": "image/png",
"width": 1024,
"height": 1024
}
]
},
"settled": true
},
"request_id": "req_example_record"
}Download from url before expiresAt. Need a fresh link later? Ask POST /common/download-url.
Verify a callback
import { createHash, createHmac, timingSafeEqual } from "node:crypto";
import express from "express";
const app = express();
// express.raw keeps the exact bytes that were signed; express.json would not match.
app.post("/hooks/popnow", express.raw({ type: "application/json" }), (req, res) => {
const timestamp = req.header("X-Webhook-Timestamp");
const signature = req.header("X-Webhook-Signature") ?? "";
const body = JSON.parse(req.body.toString("utf8"));
const taskId = body.data?.taskId ?? body.task_id;
const digest = createHash("sha256").update(req.body).digest("hex");
const expected = createHmac("sha256", process.env.POPNOW_WEBHOOK_SECRET)
.update(`${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
});With callBackUrl set, we post the finished task to you. Check the signature against the raw body before you trust it.
Send a local file
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.Public https links work as they are. Local files go through upload-url and commit first.

