Best NSFW Detection APIs Compared: 2026 Guide

#webdev #python #api #security

Choosing the right NSFW detection API can save your platform from legal liability, app store removal, and advertiser pullbacks. Here's how the top image moderation APIs compare.

Quick Comparison

API	Categories	Free Tier	Paid From	Setup
AI Engine NSFW Detect	10 (hierarchical)	30 req/mo	$12.99/mo	RapidAPI key
Amazon Rekognition	7 top-level	5K/mo (12 mo)	$0.001/image	AWS + IAM
Google Vision	5 (SafeSearch)	1K/mo	$1.50/1K	GCP + billing
Azure Content Safety	4 severity levels	5K/mo	$1.00/1K	Azure subscription
Clarifai	5 concepts	1K/mo	$1.20/1K	API key

AI Engine NSFW Detect — Python Example

import requests

url = "https://nsfw-detect3.p.rapidapi.com/nsfw-detect"
headers = {
    "x-rapidapi-host": "nsfw-detect3.p.rapidapi.com",
    "x-rapidapi-key": "YOUR_API_KEY",
    "Content-Type": "application/x-www-form-urlencoded",
}

response = requests.post(url, headers=headers, data={"url": "https://example.com/photo.jpg"})
result = response.json()

for label in result["body"]["ModerationLabels"]:
    print(f"{label['Name']}: {label['Confidence']:.1f}%")

10 categories with hierarchical sub-labels: Explicit Nudity, Suggestive, Violence, Visually Disturbing, Rude Gestures, Drugs, Tobacco, Alcohol, Gambling, Hate Symbols.

Three-Tier Moderation Pipeline

BLOCK_CATEGORIES = {"Explicit Nudity", "Violence", "Hate Symbols"}
WARN_CATEGORIES = {"Suggestive", "Drugs", "Alcohol", "Tobacco"}

def moderate(image_url: str) -> str:
    response = requests.post(url, headers=headers, data={"url": image_url})
    labels = response.json()["body"]["ModerationLabels"]

    for label in labels:
        if label["Name"] in BLOCK_CATEGORIES and label["Confidence"] > 80:
            return "block"
    for label in labels:
        if label["Name"] in WARN_CATEGORIES and label["Confidence"] > 70:
            return "warn"
    return "allow"