Free AI writing-feedback tool by Cambridge University Press & Assessment (Sept 2016); assigns CEFR A1–C2 levels to EFL essays and highlights errors by type; grounded in Yannakoudakis et al. (2018) peer-reviewed model and the open Write & Improve Corpus 2024 (23,000+ essays).
Write & Improve is a free automated writing-feedback tool developed by Cambridge University Press & Assessment, launched publicly in September 2016 after more than three years of beta testing. It assigns CEFR proficiency levels (A1-C2) to submitted English texts and highlights errors by type (grammar, vocabulary, spelling), using a model trained on the 30-million-word Cambridge Learner Corpus and validated in peer-reviewed research (Yannakoudakis et al., 2018). The tool is free with no mandatory account for basic use and is used for self-study and in EFL classrooms across 100+ countries.
Results
A 2025 study published in Language Teaching (Cambridge Core) found AI-to-human-rater agreement on CEFR level comparable to inter-rater reliability between two trained human examiners. In 2024 Cambridge released the Write & Improve Corpus 2024, an openly licensed dataset of 23,000+ annotated essays (3.5 million+ word tokens) from 766 learners, enabling further research benchmarking.
Implementation
Implementation detail (cost, timeline, staffing, conditions for success) is not yet available for this practice.
Data sources
Where this practice's information was retrieved from, and when.