With AI image generators producing increasingly photorealistic output, telling a real photo apart from a generated one by eye alone is no longer reliable — but the files themselves often still carry technical fingerprints.
This guide covers how to detect AI-generated images for free, and explains exactly what signals the detector looks for.
Key Takeaway: The strongest signal isn't pixel analysis — it's metadata. Most AI generators embed software signatures (like "Midjourney" or "DALL-E") directly into EXIF fields, and finding one of these is treated as a near-certain match before any pixel-level analysis even runs.
What the Detector Actually Checks
| Signal | What it indicates |
|---|---|
| EXIF software/creator fields | Direct generator name match (Midjourney, DALL-E, Stable Diffusion, Firefly, Flux, etc.) |
| Camera/lens/GPS metadata present | Strong evidence of a real camera photo |
| Pixel noise level | Real camera sensors produce natural noise; very smooth pixels suggest AI generation |
| Color entropy | AI images sometimes show a narrower color range than real photos |
| Common AI dimensions | Sizes like 512×512 or 1024×1024 are typical generator output resolutions |
Why Results Can Be Uncertain
If metadata has been stripped — which happens automatically when an image is re-saved, screenshotted, or shared through some social platforms — the detector loses its strongest signal and has to rely on pixel-level patterns alone, which are probabilistic rather than definitive.
Tip: For the most reliable result, analyze the original file directly from the source (camera or AI generator) before it's been compressed, cropped, or re-uploaded anywhere.
Step by Step: How to Detect an AI-Generated Image
TinyPNG Now includes a free AI image detector that runs entirely in your browser.
- Open the AI Image Detector tool and drop in the image you want to check.
- Wait a few seconds while it reads metadata and analyzes pixel patterns.
- Review the verdict, AI probability score, and the specific signals detected.
Frequently Asked Questions
Is this AI detector 100% accurate?
No. Browser-based analysis gives a directional result, not a guarantee. Accuracy is highest on uncompressed original files with full EXIF metadata intact.
What image formats does the AI detector support?
JPG, PNG, and WebP are fully supported. For best results, use the original uncompressed file before any editing or re-export.
Does the AI detector upload my image?
No. All analysis runs entirely in your browser. Your image is never sent to any server.
Can it detect Midjourney, DALL-E, and Stable Diffusion images?
Yes. The detector specifically looks for metadata signatures from Midjourney, DALL-E, Stable Diffusion, Adobe Firefly, Flux, and other major AI generators.
Summary: Open the free TinyPNG Now AI image detector, upload the file, review the score and signals — free, private, and instant.
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