Google Nano Banana 2 Text To Image Fast API Documentation

Google Nano Banana 2 Text To Image Fast API Documentation

Playground

Google Nano Banana 2 Fast (Gemini 3.1 Flash Image) is the cheapest Nano Banana 2 option, starting at just $0.045 per image. Delivers fast text-to-image generation with 2K default output and 4K support. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing.

Features

Nano Banana 2 Text-to-Image Fast (Gemini 3.1 Flash Image) is the cheapest Nano Banana 2 option, starting at just $0.045 per image. It delivers faster generation times while maintaining high visual quality, with 2K resolution by default.

Why Choose This?

• Lowest cost Nano Banana 2 The cheapest Nano Banana 2 option at just $0.045 per image.

• Speed-optimized Faster generation times compared to the standard variant.

• High-resolution default 2K output by default with 4K available for maximum detail.

• Flexible aspect ratios Multiple options including 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, and 8:1.

• Cinematic quality Excels at photorealistic scenes with atmospheric lighting and anamorphic lens effects.

• Prompt Enhancer Built-in tool to automatically improve your descriptions.

• Format choice Export in PNG or JPEG format.

Parameters

How to Use

1. Write your prompt — describe the image in detail, including style, lighting, and composition.
2. Choose aspect ratio (optional) — select a preset or leave empty for default.
3. Select resolution — choose 2K (default) or 4K based on your needs.
4. Choose output format — PNG for transparency support, JPEG for smaller file size.
5. Use Prompt Enhancer (optional) — click to automatically refine your description.
6. Run — submit and download your generated image.

Pricing

Best Use Cases

• Cinematic Imagery — Generate atmospheric scenes with anamorphic lens effects and film-like quality.
• Character Portraits — Create detailed character illustrations with specific attributes.
• Social Media Content — Produce eye-catching visuals for various platforms with flexible aspect ratios.
• Marketing & Ads — Generate professional images for campaigns and promotions.
• Concept Art — Visualize creative ideas with photorealistic rendering.

Pro Tips

• Use cinematic language like “anamorphic lens look,” “neon signs reflected in puddles,” or “rainy Tokyo street at night” for atmospheric results.
• Be specific about character attributes (hair color, clothing, accessories) for consistent results.
• Match aspect ratio to your target platform: 9:16 for Stories/Reels, 16:9 for banners, 1:1 for feeds.
• Try the Prompt Enhancer to automatically improve your descriptions.

Notes

• Prompt is the only required field.
• If aspect_ratio is not selected, the model uses a default ratio.
• Ensure your prompts comply with Google’s Safety Guidelines.

Related Models

• Nano Banana 2 Text-to-Image — Standard variant with 0.5K/1K/2K/4K resolution options.
• Nano Banana 2 Edit Fast — Fast image editing.
• Nano Banana 2 Edit — Image editing capabilities.
• Nano Banana Pro Text-to-Image — Pro tier with enhanced quality.

Authentication

For authentication details, please refer to the Authentication Guide.

API Endpoints

Submit Task & Query Result

set -euo pipefail

export WAVESPEED_API_KEY="your-api-key"

REQUEST_BODY=$(cat <<'JSON'
{
  "prompt": "A cinematic ocean wave at sunrise, highly detailed",
  "aspect_ratio": "1:1",
  "resolution": "2k",
  "enable_web_search": false,
  "output_format": "png"
}
JSON
)

# 1. Submit the prediction once. Never retry this request automatically:
# a retry after an unclear failure can create a second, billed task.
CHECK='The task may already exist. Check History or the predictions list before submitting again.'
if ! SUBMIT_RESPONSE=$(curl --silent --show-error --fail-with-body \
  --connect-timeout 10 --max-time 60 \
  -X POST "https://api.wavespeed.ai/api/v3/google/nano-banana-2/text-to-image-fast" \
  -H "Authorization: Bearer ${WAVESPEED_API_KEY}" \
  -H "Content-Type: application/json" \
  -d "${REQUEST_BODY}"); then
  printf 'Submit failed. %s\n' "${CHECK}" >&2
  exit 1
fi

TASK=$(printf '%s' "${SUBMIT_RESPONSE}" | jq 'if type == "object" and has("data") then .data else . end')
PREDICTION_ID=$(printf '%s' "${TASK}" | jq -r '.id // empty')
if [ -z "${PREDICTION_ID}" ]; then
  printf 'Submission response did not contain a prediction id. %s\n' "${CHECK}" >&2
  exit 1
fi
RESULT_URL="https://api.wavespeed.ai/api/v3/predictions/${PREDICTION_ID}/result"

# 2. Poll until the prediction reaches a final status.
BODY_FILE=$(mktemp)
trap 'rm -f "${BODY_FILE}"' EXIT
while true; do
  # Transient errors (429, 5xx) are retried, honoring Retry-After.
  HTTP_CODE=$(curl --silent --show-error --fail-with-body \
    --connect-timeout 10 --max-time 60 --retry 5 --retry-delay 2 \
    --output "${BODY_FILE}" --write-out '%{http_code}' \
    "${RESULT_URL}" \
    -H "Authorization: Bearer ${WAVESPEED_API_KEY}" || true)
  case "${HTTP_CODE}" in
    2??) ;;
    000|429|5??)  # dropped connection or temporary error: keep polling
      printf 'Task %s: HTTP %s, polling again in 10s\n' "${PREDICTION_ID}" "${HTTP_CODE}" >&2
      sleep 10; continue ;;
    *) printf 'Task %s: HTTP %s\n' "${PREDICTION_ID}" "${HTTP_CODE}" >&2
      cat "${BODY_FILE}" >&2; exit 1 ;;
  esac
  RESULT=$(jq 'if type == "object" and has("data") then .data else . end' "${BODY_FILE}")
  STATUS=$(printf '%s' "${RESULT}" | jq -r '.status // empty')

  case "${STATUS}" in
    completed) printf '%s\n' "${RESULT}" | jq '.outputs'; break ;;
    failed|cancelled|timeout|deleted)
      printf 'Task %s ended with status %s\n' "${PREDICTION_ID}" "${STATUS}" >&2
      printf '%s\n' "${RESULT}" | jq . >&2; exit 1 ;;
    *) sleep 2 ;;
  esac
done

Parameters

Task Submission Parameters

Request Parameters

Every model also accepts the global request options enable_sync_mode and enable_base64_output; see their pages for details.

Response Parameters

Result Request Parameters

Result Response Parameters