AI Image Detection

AI Image Detection

curl --request POST \
  --url https://nano-gpt.com/api/v1/ai-detection/image

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://nano-gpt.com/api/v1/ai-detection/image",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://nano-gpt.com/api/v1/ai-detection/image"

	req, _ := http.NewRequest("POST", url, nil)

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://nano-gpt.com/api/v1/ai-detection/image")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)

response = http.request(request)
puts response.read_body

POST

api

ai-detection

image

AI Image Detection

curl --request POST \
  --url https://nano-gpt.com/api/v1/ai-detection/image

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://nano-gpt.com/api/v1/ai-detection/image",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://nano-gpt.com/api/v1/ai-detection/image"

	req, _ := http.NewRequest("POST", url, nil)

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://nano-gpt.com/api/v1/ai-detection/image")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)

response = http.request(request)
puts response.read_body

Overview

Use POST /api/v1/ai-detection/image to check whether an image is AI-generated. Send the image as base64 or as a direct link to the image file. Detection is run by Pangram.

To check an image without code, use the AI image detector on nano-gpt.com. It uses the same detectors and prices.

Endpoint

POST https://nano-gpt.com/api/v1/ai-detection/image

Authentication

An API key is required. Browser sessions are not accepted.

Authorization: Bearer YOUR_API_KEY
x-api-key: YOUR_API_KEY

Request Body

Send a link:

{
  "image_url": "https://example.com/photo.jpg",
  "model": "pangram-image-1"
}

Or send the image itself:

{
  "image": "data:image/png;base64,iVBORw0KGgo...",
  "model": "pangram-image-flash-1"
}

Parameters

Send exactly one of image or image_url.

Field	Type	Required	Default	Description
`image`	string	One of `image` / `image_url`	-	Base64-encoded image, or a `data:image/png;base64,...` data URL. A data URL’s type must match the file’s bytes.
`image_url`	string	One of `image` / `image_url`	-	Public `http` or `https` link to the image file.
`model`	string	No	`pangram-image-1`	Detection model. Allowed values: `pangram-image-1`, `pangram-image-flash-1`.

Models and Pricing

Model	Price per image
`pangram-image-1`	$0.3125
`pangram-image-flash-1`	$0.0625

Your balance and any API key spend limits must cover the price before the image is read. You are charged only when a result is returned; a detector failure is not charged. If you disconnect after the image reaches the detector, the check still finishes and is charged. For API keys with an allowed-model list, the list must include pangram-image-detection (for pangram-image-1) or pangram-image-flash-detection (for pangram-image-flash-1).

Image Rules

Formats: PNG, JPEG or WebP.
Size: up to 32 MiB (33,554,432 bytes).
The JSON request body is limited to 4,400,000 bytes, so base64 images above about 3.3 MB must be sent with image_url.
image_url must be a direct link to the image file, not a web page that shows it. Links with a username or password are refused. The download times out after 30 seconds.
Link downloads count against the same per-account and per-IP request and byte quotas as other NanoGPT remote file fetches.
Up to 10 AI detection checks can run at once per account. This limit is shared with text detection.

Response

{
  "object": "ai_detection.image",
  "model": "pangram-image-1",
  "prediction": "Likely AI",
  "ai_likelihood": 0.8,
  "confidence": "High",
  "detection_source": "model",
  "heatmap": null,
  "metadata": {},
  "thumbnail": null,
  "version": "detector version",
  "cost_usd": 0.3125,
  "pricing": {
    "amount": 0.3125,
    "currency": "USD"
  }
}

Field	Type	Description
`object`	string	Always `ai_detection.image`.
`model`	string	Model used.
`prediction`	string	One of `AI Detected`, `Likely AI`, `Unsure`, `Likely No AI`, `No AI`, `Partially AI`.
`ai_likelihood`	number or null	Likelihood that the image is AI-generated, from 0 to 1.
`confidence`	string or null	`Low`, `Medium` or `High`.
`detection_source`	string	`model` when the detector judged the pixels, `c2pa` when the result comes from the file’s C2PA content credentials.
`heatmap`	object or null	`{ "grid": number[][], "patch_stride": number }`. `grid` holds an AI score from 0 to 1 for each image patch, row by row.
`metadata`	object	File metadata found by the detector, such as Content Credentials (`c2pa`), camera and software.
`thumbnail`	object or null	`{ "data_url": string, "width": number, "height": number }`.
`version`	string or null	Detector version.
`cost_usd`	number	Price of the check in USD.
`pricing`	object	Amount charged and the balance it was charged to (`USD` or `XNO`).

The request returns when the check finishes. The server stops waiting for the detector about 280 seconds after the request starts and returns 504 with code timeout.

Example

curl -sS -X POST "https://nano-gpt.com/api/v1/ai-detection/image" \
  -H "Authorization: Bearer $NANOGPT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"image_url":"https://example.com/photo.jpg","model":"pangram-image-1"}'

Send a local file as base64:

printf '{"image":"%s"}' "$(base64 < photo.png | tr -d '\n')" > request.json

curl -sS -X POST "https://nano-gpt.com/api/v1/ai-detection/image" \
  -H "Authorization: Bearer $NANOGPT_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @request.json

Common Errors

Errors use this shape:

{
  "error": {
    "message": "Use a PNG, JPEG or WebP image.",
    "code": "unsupported_image_type"
  }
}

Status	Code	Description
400	`invalid_json`	Request body is not valid JSON.
400	`invalid_request`	Neither or both of `image` and `image_url` were sent.
400	`invalid_model`	`model` is not `pangram-image-1` or `pangram-image-flash-1`.
400	`invalid_image`	`image` is not valid base64 or a valid base64 data URL.
400	`invalid_image_url`	The link is not a public `http`/`https` URL, or no image could be loaded from it.
401	`missing_api_key`	API key is required.
401	`invalid_api_key`	API key is not valid.
402	`insufficient_balance`	Balance is too low for the check.
403	`paid_features_disabled`	Paid models are disabled for API use on this subscription.
403	`model_not_allowed`	The API key’s allowed-model list does not include this detection model.
403	`zdr_provider_required`	The API key or request requires Zero Data Retention (ZDR), for example `"provider": { "zdr": true }`. AI detection is not available on ZDR requests.
413	`request_body_too_large`	JSON body is over 4,400,000 bytes.
413	`image_too_large`	Image is over 32 MiB.
413	`file_too_large`	The detector refused the file as too large.
415	`unsupported_image_type`	Image is not PNG, JPEG or WebP, or a data URL’s type does not match the file.
422	`invalid_image`	The detector could not read the image.
422	`unsafe_content`	The file can’t be checked.
429	`link_rate_limited`	Too many link fetches. Try again later.
429	`too_many_concurrent_requests`	10 AI detection checks are already running for this account. Check `Retry-After`.
429	API key limit code	An API key spend limit was reached, for example `daily_usd_limit_exceeded`. Check `Retry-After`.
502	`upstream_error`, `upstream_task_failed`, `upstream_malformed_result`, `upstream_missing_task_id`	The detector failed. Not charged.
503	`link_quota_unavailable`	Link checks are temporarily unavailable.
503	`service_unavailable`, `service_busy`	The detector is unavailable or busy. Try again later.
504	`timeout`	The detector did not finish in time.

Get Started

Endpoint Examples

API Reference

Miscellaneous

Integrations

Overview

Endpoint

Authentication

Request Body

Parameters

Models and Pricing

Image Rules

Response

Example

Common Errors

​Overview

​Endpoint

​Authentication

​Request Body

​Parameters

​Models and Pricing

​Image Rules

​Response

​Example

​Common Errors

Overview

Endpoint

Authentication

Request Body

Parameters

Models and Pricing

Image Rules

Response

Example

Common Errors