Frequently asked questions
Plain answers about SynthGuard's tools, pricing, privacy, and how detection actually works.
General
What is SynthGuard?+
SynthGuard is a privacy-first anti-AI-detection toolkit. Image humanizer, video humanizer, text humanizer, and a free AI image detector — all running in your browser, no uploads.
Why browser-only?+
Because the moment your content touches a server, you've lost control of it. Browser-only means there's no server log, no training corpus contribution, no data breach risk.
What's in the free tier?+
3 humanization runs per week across all tools, plus unlimited use of the AI image detector. Pro at €19/month gets 50 runs; Studio at €49/month is unlimited.
What data does SynthGuard store?+
Account email, plan tier, weekly credit count, and an event log of when humanizations ran (no content). That's it.
Text humanizer
Which text detectors does the humanizer beat?+
Tested against GPTZero, Originality.ai, Turnitin, Winston AI, Copyleaks, ZeroGPT. Detection landscape changes — always verify.
Which languages are supported?+
English and German with native phrase dictionaries. Other languages get the structural layers (restructure, punctuation) but not phrase-replace.
Will the humanizer change my meaning?+
No. All layers are meaning-preserving by design. Phrase-replace uses semantically equivalent substitutions, restructure keeps clauses intact.
What's the maximum document length?+
There's no hard cap. 50,000+ words processes in seconds because everything runs locally.
What's the burstiness meter?+
Live measurement of sentence-length variance — the metric most AI detectors score. Above ≈0.55 generally reads as human.
Image humanizer
Which image detectors does it beat?+
Hive Moderation, Sightengine, Illuminarty, and the platform-side classifiers used by Instagram, TikTok, Reddit moderation bots, OnlyFans, Etsy.
Does humanization hurt image quality?+
At default settings, no visible loss. Strict profile adds slightly more perturbation but stays below human perception threshold.
What does the pipeline actually do?+
Strips C2PA, injects PRNU sensor noise, disrupts FFT signatures, generates realistic EXIF, perturbs texture statistics, plus refinement passes. Some layers are intentionally not detailed publicly.
Can it remove SynthID watermarks?+
It disrupts the synchronization signal SynthID relies on, which collapses detection to chance. The image looks identical.
Can I batch-process images?+
Yes — drop multiple files into the humanizer and they process in parallel via Web Workers.
Video humanizer
Which video formats are supported?+
MP4, MOV, WebM. Output is always MP4 with stripped container metadata.
What's the maximum video length?+
Hard limit is browser memory. Practical limit is 60–90 seconds at 1080p on most machines.
Will the video quality drop?+
Mild — re-encoding always costs a small amount. Output is calibrated to look the same to viewers.
How many credits does a video cost?+
1 video = 2 credits. Free plan gets 1 video per week (3 credits, video uses 2).
AI image detector
Why is the detector free?+
Because verifying your humanized image scores as human is the natural last step of the workflow. Charging for it would defeat the purpose.
How accurate is the detector?+
It scores on multiple signals (PRNU, FFT, EXIF, texture statistics) and returns a 0–100 confidence. Rigorous on current AI generators, less reliable on edge cases like edited real photos.
Does the detector use credits?+
No — unlimited use even on the free plan.
Does the detector upload my image?+
No. Same architecture as the rest of the suite — all analysis runs in your browser.
Billing & account
Can I cancel anytime?+
Yes. Cancel from /hub/account or use the public /cancel-contract form. No login required for the form (compliant with §312k BGB).
Refund policy?+
EU statutory withdrawal period applies. After that, prorated refunds for unused time on annual plans only.
When do credits reset?+
ISO Monday 00:00 UTC. So on Monday morning everyone is back to their plan's weekly cap.
Are there team plans?+
Not yet. On the roadmap.