| Criteria | Sapling | ai-detector.co |
|---|---|---|
| Built for | CX teams, writers inside the Sapling suite | Anyone with a text and a question |
| Sentence-level detail | Yes, per-sentence highlighting | No, whole-text reading |
| Price | Free tier with limits, paid suite | Free, daily fair-use limit |
| Account required | For full features | Never |
| Verdict presentation | Percentage plus highlighted sentences | 0 to 100 dial with explicit inconclusive band |
| Honest shared limitation | Sentence-level scores are noisier than document scores on every engine, including Sapling’s | We avoid sentence claims entirely for that reason |
The case for Sapling
Per-sentence highlighting is genuinely useful when your question is which parts of this draft need rewriting rather than is this machine written. Editors doing surgical revision get real value from seeing probability distributed across the text. Sapling also publishes an API and developer documentation, and its detector holds its own on the standard clear cases. If that workflow is your workflow, use Sapling; this page will not pretend otherwise.
The honest caveat on sentence scores
Statistical detection gets weaker as samples get shorter, and a sentence is a very short sample. Per-sentence probabilities are therefore the noisiest output any detector produces, which Turnitin learned publicly when its sentence-level false positive disclosures forced a recalibration. Treat highlighted sentences as suggestions for attention, never as a list of the AI sentences. Our tool reports document-level readings only, because that is the granularity the math actually supports; the reasoning is laid out in how AI detectors work.
Choosing between them
Editing workflow with revision targeting: Sapling. Fast honest verdict with zero setup and explicit uncertainty: here. Either way, cross-check anything consequential on a second engine, and read the false positives guide before acting on any score, from any vendor, against any person.
Sapling beyond the detector
Sapling is not primarily a detection company. Its core business is writing assistance for customer-facing teams: autocomplete and quality suggestions inside helpdesks and CRMs, with the AI detector as one tool in that suite. That context explains the product's strengths. It is comfortable inside other software, ships a clean developer API with per-sentence output, and treats detection as an editing aid rather than an enforcement weapon. If your team already lives in Sapling for CX writing, using its detector is the path of least resistance and a perfectly reasonable one.
Sentence-level scores: power and noise
Sapling's signature output is a per-sentence probability overlay, and it is genuinely useful for revision: it shows you which passages carry the strongest machine texture so you can rewrite exactly there. The caveat is statistical and applies to every engine that offers the feature. A sentence is a tiny sample, and classifier confidence on tiny samples swings wildly. Turnitin learned this publicly when its sentence-level false positive disclosures forced a recalibration of how scores were presented. Use sentence highlights to direct your attention, never to compile a list of the AI sentences, and treat any single highlighted sentence in isolation as noise. Document-level readings, which are what this site reports, are the granularity the underlying math actually supports.
How we compared
Our standard three sample sets went through both tools, and we reviewed both vendors' published methodology and data practices. Agreement on clear cases, divergence on human-revised drafts, no meaningful accuracy gap either direction on our samples. The choice between them is a workflow choice: sentence-level editing aid inside a writing platform, or a fast standalone reading with the uncertainty printed on the dial.
Developer notes: the API shapes compared
Sapling ships a documented detection API today: text in, an overall score plus per-sentence probabilities out, with SDKs and standard key auth. It is a reasonable integration if you need sentence granularity and are comfortable with an external dependency for a statistical signal. Our API is planned rather than live, and the published shape is deliberately simpler: one integer score, a verdict string and a class, with the inconclusive band preserved in the payload so client software cannot quietly round uncertainty away. If you are building today, Sapling is the available option; if your build can wait, decide whether your application needs sentence noise or document honesty, because that is the real difference between the two shapes.
Form your own verdict: paste the same text into both tools and compare the readings.
Run a free scanWe build ai-detector.co, so read this comparison knowing who wrote it. We link Sapling directly so you can verify every claim, and we have kept their strengths in the table on purpose.