Real-ESRGANFastHigh

Real-ESRGAN

The classic image upscaler (94M+ runs). Real-ESRGAN super-resolution up to 10x with optional GFPGAN face enhancement — the go-to default for cleanly enlarging photos and AI images.

5 credits

per image

Battle-tested upscaler (94M+ runs)

Scale factor up to 10x

Optional GFPGAN face enhancement

Faithful, artifact-free enlargement

Very low cost (6 credits per image)

Run it right now

Test this model instantly in the Console Playground — no code required

Use with AI Assistant

Copy usage instructions for Claude, ChatGPT, or other AI

llms.txtllms.txt ↗

Quick Start

curl -X POST "https://api.core.today/v1/predictions" \
  -H "Content-Type: application/json" \
  -H "X-API-Key: cdt_your_api_key" \
  -d '{
  "model": "nightmareai/real-esrgan",
  "input": {
    "image": "https://example.com/photo.jpg",
    "scale": 4
  }
}'

Parameters

Parameter	Type	Required	Default	Description
`image`	string	Yes	-	Input image to upscale
`scale`	number	No	4	Factor to scale the image by (up to 10)
`face_enhance`	boolean	No	false	Run GFPGAN face enhancement along with upscaling

How to Provide File Input

There are 3 ways to provide files for the image parameter:

Recommended

Direct Upload (Multipart)

Attach files directly to POST /v1/predictions/upload. No separate upload step needed.

curl -X POST "https://api.core.today/v1/predictions/upload" \
  -H "X-API-Key: cdt_your_api_key" \
  -F "model=nightmareai/real-esrgan" \
  -F 'input={"prompt":"your prompt here"}' \
  -F "file:image=@your_file.png"

Image URL

Pass a publicly accessible URL directly. You can also use file_url from the Storage API.

{
  "model": "nightmareai/real-esrgan",
  "input": {
    "prompt": "your prompt here",
    "image": "https://example.com/image.jpg"
  }
}

See the File Upload docs for more upload methods including Presigned URLs.

Common Parameters

Common parameters used when calling POST /v1/predictions.

Parameter	Type	Required	Default	Description
`model`	string	Yes	-	Model identifier
`input`	object	Yes	-	Object containing the model-specific parameters from the table above
`output_folder`	string	No	-	Folder path for output files (max 256 chars, '..' not allowed)
`webhook_url`	string	No	-	Webhook URL to call on completion
`is_public`	boolean	No	false	If true, output files are also available via permanent public URLs

Examples

4x Photo Upscale

Standard 4x upscale of a photo

curl -X POST "https://api.core.today/v1/predictions" \
  -H "Content-Type: application/json" \
  -H "X-API-Key: cdt_your_api_key" \
  -d '{
  "model": "nightmareai/real-esrgan",
  "input": {
    "image": "https://example.com/photo.jpg",
    "scale": 4
  }
}'

Portrait Upscale with Face Enhancement

Upscale a portrait and restore facial details

curl -X POST "https://api.core.today/v1/predictions" \
  -H "Content-Type: application/json" \
  -H "X-API-Key: cdt_your_api_key" \
  -d '{
  "model": "nightmareai/real-esrgan",
  "input": {
    "image": "https://example.com/portrait.jpg",
    "scale": 2,
    "face_enhance": true
  }
}'