diff --git a/src/app/api/generate/providers/__tests__/newapiwg.test.ts b/src/app/api/generate/providers/__tests__/newapiwg.test.ts
index 8bcd9079..787907fc 100644
--- a/src/app/api/generate/providers/__tests__/newapiwg.test.ts
+++ b/src/app/api/generate/providers/__tests__/newapiwg.test.ts
@@ -528,6 +528,29 @@ describe("NewApiWG generation payloads", () => {
     expect(capturedBody!.aspect_ratio).toBeUndefined();
   });
 
+  it("raises Seedream 1K requests to the provider minimum pixel size", async () => {
+    const result = await generateWithNewApiWG("test-key", "https://newapi.example/v1", makeInput({
+      model: {
+        id: "doubao-seedream-4-5-251128",
+        name: "Doubao Seedream 4.5",
+        description: null,
+        provider: "newapiwg",
+        capabilities: ["text-to-image", "image-to-image"],
+      },
+      prompt: "draw a wide maze",
+      parameters: {
+        resolution: "1K",
+        imageSize: "1K",
+        aspectRatio: "21:9",
+        aspect_ratio: "21:9",
+      },
+    }));
+
+    expect(result.success).toBe(true);
+    expect(capturedBody!.model).toBe("doubao-seedream-4-5-251128");
+    expect(capturedBody!.size).toBe("2936x1264");
+  });
+
   it("blocks cached Doubao chat models before calling media generation endpoints", async () => {
     const result = await generateWithNewApiWG("test-key", "https://newapi.example/v1", makeInput({
       model: {
diff --git a/src/app/api/generate/providers/newapiwg.ts b/src/app/api/generate/providers/newapiwg.ts
index 72828c43..e633c850 100644
--- a/src/app/api/generate/providers/newapiwg.ts
+++ b/src/app/api/generate/providers/newapiwg.ts
@@ -420,6 +420,7 @@ const NEWAPIWG_IMAGE_RESOLUTION_PIXELS: Record<string, number> = {
   "2K": 2560 * 1440,
   "4K": 3840 * 2160,
 };
+const NEWAPIWG_SEEDREAM_MIN_IMAGE_PIXELS = NEWAPIWG_IMAGE_RESOLUTION_PIXELS["2K"];
 const REFERENCE_IMAGE_FETCH_TIMEOUT_MS = 30_000;
 const MAX_REFERENCE_IMAGE_BYTES = 25 * 1024 * 1024;
 
@@ -493,12 +494,44 @@ function ceilToMultiple(value: number, multiple: number): number {
   return Math.ceil(value / multiple) * multiple;
 }
 
-function resolveNewApiWGImageSize(parameters: Record<string, unknown> | undefined): string {
+function isSeedreamImageModel(modelId: string): boolean {
+  return /seedream/i.test(modelId);
+}
+
+function parsePixelSize(value: string): { width: number; height: number } | null {
+  const match = value.match(/^(\d+)x(\d+)$/i);
+  if (!match) return null;
+  const width = Number(match[1]);
+  const height = Number(match[2]);
+  if (!Number.isFinite(width) || !Number.isFinite(height) || width <= 0 || height <= 0) {
+    return null;
+  }
+  return { width, height };
+}
+
+function pixelSizeForAspectRatio(targetPixels: number, ratio: { width: number; height: number }): string {
+  const width = ceilToMultiple(Math.sqrt(targetPixels * ratio.width / ratio.height), 8);
+  const height = ceilToMultiple(Math.sqrt(targetPixels * ratio.height / ratio.width), 8);
+  return `${width}x${height}`;
+}
+
+function clampPixelSize(size: string, minPixels: number): string {
+  if (minPixels <= 0) return size;
+  const parsed = parsePixelSize(size);
+  if (!parsed || parsed.width * parsed.height >= minPixels) return size;
+  return pixelSizeForAspectRatio(minPixels, parsed);
+}
+
+function resolveNewApiWGImageSize(
+  parameters: Record<string, unknown> | undefined,
+  modelId: string
+): string {
+  const minPixels = isSeedreamImageModel(modelId) ? NEWAPIWG_SEEDREAM_MIN_IMAGE_PIXELS : 0;
   const requestedSize =
     getStringParameter(parameters, "imageSize") ??
     getStringParameter(parameters, "resolution");
   if (requestedSize) {
-    if (/^\d+x\d+$/i.test(requestedSize)) return requestedSize;
+    if (/^\d+x\d+$/i.test(requestedSize)) return clampPixelSize(requestedSize, minPixels);
 
     const targetPixels = NEWAPIWG_IMAGE_RESOLUTION_PIXELS[requestedSize];
     if (targetPixels) {
@@ -506,15 +539,13 @@ function resolveNewApiWGImageSize(parameters: Record<string, unknown> | undefine
         getStringParameter(parameters, "aspectRatio") ??
         getStringParameter(parameters, "aspect_ratio")
       );
-      const width = ceilToMultiple(Math.sqrt(targetPixels * ratio.width / ratio.height), 8);
-      const height = ceilToMultiple(Math.sqrt(targetPixels * ratio.height / ratio.width), 8);
-      return `${width}x${height}`;
+      return pixelSizeForAspectRatio(Math.max(targetPixels, minPixels), ratio);
     }
   }
 
   const explicitSize = getStringParameter(parameters, "size");
-  if (explicitSize) return explicitSize;
-  return "1024x1024";
+  if (explicitSize) return clampPixelSize(explicitSize, minPixels);
+  return clampPixelSize("1024x1024", minPixels);
 }
 
 function isImagenGenerationModel(modelId: string): boolean {
@@ -940,7 +971,7 @@ export async function generateWithNewApiWG(
   }
 
   const endpoint = `${normalizedBaseUrl}/${isVideo ? "video" : "images"}/generations`;
-  const imageSize = resolveNewApiWGImageSize(input.parameters);
+  const imageSize = resolveNewApiWGImageSize(input.parameters, input.model.id);
   const imageParameters = normalizeNewApiWGImageGenerationParameters(input.parameters);
   const rawDynamicInputs = dynamicInputsWithoutPrompt(input);
   const normalizedVideoInputs = isVideo