SynthGuard vs Undetectable.ai — modes, tools and privacy compared.
Undetectable.ai and SynthGuard both offer text rewriting. SynthGuard Light mode is local; Standard and Aggressive use the disclosed inference route for deeper rewriting.
| Feature | SynthGuard | Undetectable.ai |
|---|---|---|
| Where text is processed | Light: local; deeper modes: inference route | Service infrastructure; check current policy |
| Data handling | Mode-specific disclosure | Per current privacy policy |
| Image humanization | Yes — full pipeline | No |
| Video humanization | Yes | No |
| AI image detector | Yes — free | No |
| Pricing model | Free + $14.99/mo Pro | Subscription, per-word limits |
| Offline use after first load | Light mode only | Check current product |
| Burstiness meter | Live, in-browser | Score after rewrite |
Undetectable.ai is the most well-known text humanizer. Its rewrite quality is solid for English content, and its UI is polished. The fundamental tradeoff is that every word you paste into Undetectable.ai goes to their servers for processing. Their privacy policy lays out what they do with that data — read it before pasting anything sensitive.
SynthGuard exposes two privacy boundaries. Light mode applies deterministic edits in the browser and can continue without an inference request. Standard and Aggressive use the protected inference route for deeper rewriting and are not described as browser-only.
Both products target writing characteristics such as rhythm and predictability, but output quality and detector scores depend on language, source text and current detector versions. SynthGuard exposes before/after metrics; they are editorial aids rather than proof of authorship.
Beyond text, SynthGuard does what Undetectable.ai doesn't: image humanization (against detectors like Hive, Sightengine, Illuminarty) and video humanization. If you only need text, Undetectable.ai is a fine choice if you trust their data handling. If you want privacy or want one tool that handles text + image + video, SynthGuard is the practical pick.
Pricing: SynthGuard is free for 3 humanizations per week, $14.99/month for 50, $29/month unlimited. Undetectable.ai's pricing is per-word with monthly subscription tiers. For typical use, SynthGuard's flat pricing is cheaper.
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
Is SynthGuard's rewrite quality as good as Undetectable.ai?+
There is no universal quality or detector winner. Compare the same text, review meaning and voice, and treat detector scores as uncertain signals.
Can Undetectable.ai see my text?+
Their servers receive every word you submit. Their privacy policy describes their data handling.
Does SynthGuard work offline?+
Light mode can run locally after the page loads. Standard and Aggressive require the inference route.
Which one is better for non-English text?+
SynthGuard ships native German support. Undetectable.ai supports English primarily.
More comparisons
SynthGuard vs StealthGPT
Compare StealthGPT with SynthGuard's local Light mode and disclosed Standard/Aggressive inference modes. Verify current third-party terms before submitting sensitive text.
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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