SYNTHGUARD
    012 AI Image Detectorv1

    AI ImageDetector

    Upload a local image and review 8 browser-based signals. Files never leave your browser, and only signed-in users can access this route.

    Free analysis · 100% local · no credits used
    8 signals·~2-5s analysis·JPEG, PNG, or WebP

    AI Image Detector is sign-in only

    Eight forensic signals run entirely in your browser — but you need a free account to start an analysis session. No credits used, ever.

    3 free credits every Monday. No card.

    100% browser-only · your files never leave your device

    Free account · no credit card required

    Detector pillars

    What the eight signals actually measure

    Noise & Sensor Forensics

    Real cameras leave a noisy fingerprint with channel correlations diffusion models can't reproduce cleanly. We measure noise level and channel correlation to flag synthetic textures.

    8x8 JPEG Grid Analysis

    JPEG-encoded camera files have block-boundary regularity at the 8x8 grid. We measure that ratio and downweight it automatically when the image was downscaled and the original grid no longer applies.

    High-Frequency Energy

    Diffusion outputs are smoother than reality at fine scales. An FFT-based pass measures high-frequency texture complexity to catch over-smoothed regions invisible to the eye.

    Color Entropy & Variance

    Generated images often collapse into narrower color distributions and over-uniform local patches. We score color entropy and patch-level variance against natural-photo baselines.

    EXIF Reliability Tiers

    Metadata is graded High / Medium / Low based on what's actually present — camera, lens, GPS, timestamps, software. Pixel signals are reweighted accordingly so missing EXIF can't dominate the verdict.

    100% Local, 100% Free

    No upload, no quota, no API key. The full eight-signal analysis runs in your browser — disable your network and it still works. Detector use never costs credits.

    How it runs

    Three steps, all in your browser

    01

    Drop image

    Drop a JPEG, PNG, or WebP image anywhere on the page. The file stays on your device.

    02

    Eight signals run

    Pixel passes (noise, JPEG grid, FFT, entropy, channel correlation, patch variance) plus EXIF reliability. Cancel anytime.

    03

    Read the verdict

    0–100 likelihood score plus a per-signal breakdown showing exactly which checks pushed the score up or down.

    Detector signals

    Synthetic vs. authentic — what each signal looks like

    Signal
    Synthetic-leaning
    Authentic-leaning
    • Noise consistency
      Over-smoothed
      Natural range
    • 8x8 JPEG grid
      Weak / missing
      Camera-typical
    • Patch variance
      Uniform
      Natural variation
    • Color entropy
      Narrow palette
      Broad spread
    • R/G channel correlation
      Unusual
      Sensor-like
    • EXIF reliability
      Missing / synthetic
      Capture metadata

    FAQ

    Detector FAQ

    Is the detector accurate?

    It's a forensic aid, not a verdict. The 0–100 score combines eight independent signals with weights that adapt to EXIF reliability. Use it together with context — no public detector is bulletproof against the latest generators.

    Why is my real photo flagged as AI?

    Heavy social-media re-compression, screenshots, and aggressive editing strip the very signals that prove authenticity (EXIF, original JPEG grid, sensor noise). Try the original file straight from your camera if you have it.

    Why is an AI image scored as real?

    Img2img, upscalers, photo-style LoRAs and post-processing through real EXIF can mask diffusion artefacts. We surface every signal individually so you can spot suspicious EXIF or unnaturally low channel correlation even when the total score is moderate.

    Does this cost credits?

    No. The detector is free for every signed-in user — no weekly quota, no per-run charge. Only the Photo, Video and Text humanizers use credits.

    Does my image get uploaded?

    Never. Decoding, EXIF parsing and all eight signal passes run in your browser. You can disable your network and the analysis still completes.

    Which formats are supported?

    JPEG, PNG, or WebP. iPhone HEIC and AVIF aren't supported yet — export or convert the image to JPEG or PNG first, then run the detector.

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