Sapling

Sapling's AI Detector scores pasted text, uploaded PDFs and DOCX files, or a selection made through its Chrome extension, and returns the probability that the text was generated by a model such as ChatGPT or Gemini. It does not include a plagiarism or originality-checking module of its own; it is purely a machine-generated-text detector, sold alongside Sapling's separate grammar checker, autocomplete, and rephrase tools under one account.

A scan produces an overall AI-generation percentage plus a per-sentence view that flags cliché or low-perplexity sentences as more likely to be AI-written, using complementary whole-text and sentence-level techniques that Sapling recommends reading together rather than relying on either alone. Results can be shared via a link that expires after three days, and the detector supports PDF and DOCX uploads in addition to pasted text. Sapling publishes a changelog of detector updates (most recently naming coverage for GPT-5, Claude 4.5, Gemini 2.5, DeepSeek-V3, and Qwen3) and a technical whitepaper describing its token-level classification and perplexity-scoring approach, along with false-positive/false-negative analysis on a held-out evaluation set.

The free check (2,000 characters, no account needed) suits anyone who wants a quick one-off answer, while registering unlocks a free one-month trial of Sapling Pro for longer documents. The tool is positioned generally for educators, SEO practitioners, and reviewers of user-generated content rather than any single vertical, and its detection API and MCP server target developers who want to wire AI checks into an existing workflow, such as an applicant-tracking system for resume screening.