Google Nano Banana 2.1 Text To Image API Documentation

Google Nano Banana 2.1 Text To Image API Documentation

Playground

Try it on WaveSpeedAI!

Google Nano Banana 2.1 is the latest Nano Banana image generation model, with gains in visual design, subject consistency and prompt adherence, cleaner text rendering, 1K to 4K output and optional web search. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing.

Features

Nano Banana 2.1 Text-to-Image is Google’s latest Nano Banana AI image generation model. Google reports that it outperforms its previous image models across the board, with notable leaps in visual design and subject consistency, tighter prompt adherence and cleaner text rendering.


Why Choose This?

  • Google’s newest Nano Banana Upgraded over Nano Banana 2 in visual design, subject consistency and prompt adherence.

  • Cleaner text rendering Sharper labels, signs and typography inside the image.

  • Multi-resolution support Output in 1K, 2K, or 4K resolution based on your needs.

  • Flexible aspect ratios Fourteen options: 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.

  • Web & image search grounding Optionally let the model use current information and real reference images from the web.

  • Format choice Export in PNG or JPEG format.


Parameters

ParameterRequiredDescription
promptYesText description of the desired image
aspect_ratioNoAspect ratio: 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
resolutionNoOutput resolution: 1k (default), 2k, 4k
enable_web_searchNoEnable web search to enhance generation with real-time info (default: false)
enable_image_searchNoEnable image search to ground the generation in real reference images (default: false)
output_formatNoOutput format: png (default), jpeg

How to Use

  1. Write your prompt — describe the image in detail, including subject, composition, lighting, style and any text in quotes.
  2. Choose aspect ratio (optional) — select a preset or leave empty for the default 1:1.
  3. Select resolution — choose 1K, 2K, or 4K based on your needs.
  4. Enable web or image search (optional) — for prompts that depend on current real-world information or how real things look.
  5. Choose output format — PNG or JPEG.
  6. Run — submit and download your generated image.

Pricing

ResolutionCost
1k$0.05
2k$0.075
4k$0.15
Web search+$0.014
Image search+$0.014

Best Use Cases

  • Design-heavy visuals — Posters, social graphics and packaging mockups where layout and typography matter.
  • Character & product consistency — Keep the same subject recognizable across a series.
  • Marketing & Ads — Campaign images with clean in-image copy.
  • Infographics & signage — Clear labels and text elements.
  • Concept Art — Visualize complex, multi-part ideas faithfully.

Pro Tips

  • Spell out the whole brief in one prompt — 2.1 follows long, multi-part instructions closely.
  • Put exact on-image text in quotes and say where it goes.
  • Match aspect ratio to your target platform: 9:16 for Stories/Reels, 16:9 for banners, 1:8 / 8:1 for skyscraper ads.
  • Draft at 1K, then re-run the final prompt at 2K or 4K.

Notes

  • Prompt is the only required field.
  • If aspect_ratio is not selected, the output is 1:1.
  • Ensure your prompts comply with Google’s Safety Guidelines.

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": "1k",
  "enable_web_search": false,
  "enable_image_search": false,
  "output_format": "png"
}
JSON
)

# 1. Submit the prediction.
SUBMIT_RESPONSE=$(curl --silent --show-error --fail-with-body \
  -X POST "https://api.wavespeed.ai/api/v3/google/nano-banana-2.1/text-to-image" \
  -H "Authorization: Bearer ${WAVESPEED_API_KEY}" \
  -H "Content-Type: application/json" \
  -d "${REQUEST_BODY}")

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 "${PREDICTION_ID}" ]; then
  printf 'Submission response did not contain a prediction id
' >&2
  exit 1
fi
RESULT_URL="https://api.wavespeed.ai/api/v3/predictions/${PREDICTION_ID}/result"

# 2. Poll until the prediction finishes.
while true; do
  RESPONSE=$(curl --silent --show-error --fail-with-body \
    "${RESULT_URL}" \
    -H "Authorization: Bearer ${WAVESPEED_API_KEY}")
  RESULT=$(printf '%s' "${RESPONSE}" | jq 'if type == "object" and has("data") then .data else . end')
  STATUS=$(printf '%s' "${RESULT}" | jq -r '.status // empty')

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

Parameters

Task Submission Parameters

Request Parameters

ParameterTypeRequiredDefaultRangeDescription
promptstringYes-The positive prompt for the generation.
aspect_ratiostringNo-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, 8:1The aspect ratio of the generated media.
resolutionstringNo1k1k, 2k, 4kThe resolution of the output image.
enable_web_searchbooleanNofalse-If enabled, the model will use web search to enhance the generation with real-time information.
enable_image_searchbooleanNofalse-If enabled, the model will use image search to enhance the generation with real-time information.
output_formatstringNopngpng, jpegThe format of the output image.
enable_sync_modebooleanNofalse-If set to `true`, the request attempts to wait for the generated result and return outputs in the same response. If the result is not ready within the sync wait window, the API can return a timeout body while the task continues processing. This option is only available via the API and is supported only by some models.
enable_base64_outputbooleanNofalse-If set to `true`, the prediction's `output` strings are returned as **naked base64** (no `data:<mime>;base64,` prefix). When `false` (default), outputs are returned as URLs pointing to our CDN.

Response Parameters

ParameterTypeDescription
codeintegerHTTP status code (e.g., 200 for success)
messagestringStatus message (e.g., “success”)
data.idstringUnique identifier for the prediction, Task Id
data.modelstringModel ID used for the prediction
data.outputsarrayOutput values, usually URL strings; some models return text strings or structured result objects (empty when status is not completed)
data.urlsobjectObject containing related API endpoints
data.statusstringTask status. completed is successful; failed, cancelled, timeout, and deleted are failure terminal statuses.
data.created_atstringISO timestamp of when the request was created (e.g., “2023-04-01T12:34:56.789Z”)
data.errorstringError message (empty if no error occurred)
data.timingsobjectObject containing timing details
data.timings.inferenceintegerInference time in milliseconds

Result Request Parameters

ParameterTypeRequiredDefaultDescription
idstringYes-Task ID

Result Response Parameters

ParameterTypeDescription
codeintegerHTTP status code (e.g., 200 for success)
messagestringStatus message (e.g., “success”)
dataobjectThe prediction data object containing all details
data.idstringUnique identifier for the prediction
data.modelstringModel ID used for the prediction
data.outputsarray<string | object>Array of generated outputs (empty when status is not completed). Items are usually URL strings, but may be text strings or structured result objects, depending on the model.
data.urlsobjectObject containing related API endpoints
data.statusstringStatus: completed is successful; failed, cancelled, timeout, and deleted are failure terminal statuses
data.created_atstringISO timestamp of when the request was created
data.errorstringError message (empty if no error occurred)
data.timingsobjectObject containing timing details
data.timings.inferenceintegerInference time in milliseconds
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