SynthGuard vs StealthGPT — text modes and tool breadth compared.
Compare StealthGPT with SynthGuard's local Light mode and disclosed Standard/Aggressive inference modes. Verify current third-party terms before submitting sensitive text.
| Feature | SynthGuard | StealthGPT |
|---|---|---|
| Architecture | Light local; deeper modes via inference route | Check current product documentation |
| Data exposure | Mode-specific disclosure | Check current privacy policy |
| Speed | Sub-second for 5,000 words | Limited by API latency |
| Image humanization | Yes | No |
| Video humanization | Yes | No |
| Cost model | Flat $14.99/mo Pro | Token-based, scales with use |
| Languages | EN + DE native | EN primarily |
StealthGPT's approach is to use other LLMs as the humanizer — your AI text gets re-prompted through a chain of models that rewrite it in a more human voice. The output quality is good, but the architecture means your text travels through multiple third-party APIs and there's no way to know exactly what gets logged where.
SynthGuard Light mode is algorithmic: it applies deterministic browser-side edits. Standard and Aggressive use the disclosed inference route for deeper rewriting, so privacy and speed comparisons must be made mode by mode.
Speed matters at scale. StealthGPT's API roundtrip puts a floor on processing time — even a fast LLM takes 1–3 seconds per paragraph. SynthGuard processes 5,000 words in under a second because there's no network roundtrip.
If you're a high-volume user (10,000+ words a day), the cost difference is significant. StealthGPT charges per token used; SynthGuard's Pro tier is flat at $14.99/month for 50 humanizations.
The image and video humanization features are exclusive to SynthGuard — StealthGPT is text-only.
Try SynthGuard — free account, no card required
Free tier: 3 credits per week. Pro: $14.99/mo for 50 credits, all camera profiles, video export and advanced controls.
Open the humanizerFrequently asked questions
Does StealthGPT use OpenAI under the hood?+
They use multiple LLM providers; the exact mix changes. Check their current docs.
Why is SynthGuard faster?+
Light mode avoids an inference roundtrip. Standard and Aggressive trade that speed for deeper rewriting.
Is the rewrite quality similar?+
Both work on current detectors. SynthGuard's deterministic approach is more predictable; StealthGPT's LLM approach can produce more varied outputs.
Can SynthGuard handle very long documents?+
Practical limits depend on the selected mode, browser resources and plan. For long documents, process reviewable sections and preserve terminology between passes.
More comparisons
SynthGuard vs Undetectable.ai
Undetectable.ai and SynthGuard both offer text rewriting. SynthGuard Light mode is local; Standard and Aggressive use the disclosed inference route for deeper rewriting.
SynthGuard vs Humbot
Humbot is a cloud-based text humanizer. SynthGuard runs locally in your browser and adds image, video, and detection tools.
SynthGuard vs WriteHuman
WriteHuman is focused on text. SynthGuard adds local image/video tools, a local detector and text modes with clearly different processing boundaries.
SynthGuard vs Phantom
Phantom is one of the newer cloud-based text humanizers. SynthGuard offers the same humanization quality plus image and video tools, all in your browser.
SynthGuard vs Imagera AI
Imagera AI generates images with built-in imperfections. SynthGuard humanizes images you already have — from any generator — entirely in your browser.
SynthGuard vs UnmadeWithAI
UnmadeWithAI is a free, local C2PA metadata remover. SynthGuard's image tool is also local and adds camera-style noise, frequency, texture, compression and EXIF processing.
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