Moderator: On-device NSFW and Nudity Detection
On-device NSFW image classification that flags nudity before an image is uploaded, trained only on licensed and synthetic data so you can ship it commercially.
Moderator is an on-device NSFW image classifier. Moderator scores an image before it ever leaves the device, so questionable content never reaches your servers, and a five-head output lets a policy decide exactly what counts.
The real edge is the training data: every image is permissively licensed or synthetically generated, with nothing scraped from the open internet. Unlike NudeNet and most NSFW models, you can ship it in a commercial product without copyright or licensing exposure. Moderator is more accurate too, catching more NSFW than NudeNet (87.8% vs 82.6% recall) and wrongly blocking about half as many safe images (6.3% vs 12.9%) on a held-out test set.
Performance
Catches 87.8% of NSFW images and passes 93.7% of safe ones at a 6.3% false-block rate, about half NudeNet's, from an on-device model under 8 MB.
Held-out set of 464 images (75% SFW), single NSFW score at threshold 0.50, 8-crop pipeline (internal)
| Recall | Specificity | False-block | |
|---|---|---|---|
| Moderator | 87.8% | 93.7% | 6.3% |
| NudeNet | 82.6% | 87.1% | 12.9% |
Internal evaluation on a proprietary held-out set, not a published benchmark. MobileNetV4 backbone, 8.4M parameters.
Use cases
Pre-upload filtering
Screen user images on device before they leave the phone, so nothing questionable reaches your servers.
Policy control
The .standard policy counts all five detections; .allowTopless excludes exposed nipples from the score, for platforms with more permissive rules.
What it does
- Trained only on permissively licensed and synthetic images, with no scraped data, so it is safe to ship commercially.
- Scores any image for nudity on device, before it is uploaded.
- Five detection heads: exposed nipples, genitals, buttocks, nudity, and sexual activity.
- A policy decides what counts toward the NSFW score, from
.standard(all five) to.allowTopless(excludes exposed nipples).
Specs
- Accuracy
- Recall 87.8%, specificity 93.7% at threshold 0.50
- Backbone
- MobileNetV4-Conv-Medium @ 384
- Size
- ~7 MB (6-bit) to ~18 MB (fp16)
- Platforms
- iOS 17+, macOS 14+, tvOS 17+, visionOS 1+; fp32 ONNX for browser or server
A content-moderation aid, not a legal determination: pair it with human review for any decision it alone gates. Moderator covers adult content only; minors are out of scope by design and excluded from the training set.
FAQ
What is Moderator?
On-device NSFW image classification that flags nudity before an image is uploaded, trained only on licensed and synthetic data so you can ship it commercially.
Does Moderator run on device?
Yes. Moderator runs entirely on device: inference happens locally with no server call, so data never leaves the device.
Is Moderator available yet?
Moderator is in closed beta. You can request early access from its page.
How much does Moderator cost?
Every model is free up to 100k monthly active devices per SDK. Unlimited inference per user. Contact us for custom licenses.
How accurate or fast is Moderator?
Catches 87.8% of NSFW images and passes 93.7% of safe ones at a 6.3% false-block rate, about half NudeNet's, from an on-device model under 8 MB.
Early access
Tell us what you are building and we will get you set up.