Blindspot

Overview

Blindspot is a web-based English writing checker that pairs AI corrections with plain-language explanations of the grammar rules behind each error. The product, available at blindspot.study, is aimed at learners who recognize rules in theory but keep breaking them in everyday writing. Instead of only replacing a flawed phrase with a clean one, the platform names the rule, shows the corrected sentence, and connects the mistake to a focused practice set. A free entry tier, a personalized vocabulary system, and a Chrome extension complete the offering.

Key Features

• Rule-based corrections rather than silent rewrites. A sample sentence containing "didn't saw" returns the corrected "didn't see" alongside an explanation that "didn't" already marks past tense, so the following verb stays in its base form. Every flagged item carries both the fix and the reasoning behind it.
• Aggregated error patterns turned into grammar topics. Three separate sentences sharing the same underlying fault are grouped into a single topic titled "Past Simple: negative sentences," which then generates a multiple-choice drill where the learner picks the missing verb from options such as went, go, and going.
• Personal vocabulary entries with collocations and flashcards. A saved word such as "endeavour" arrives with noun and verb definitions, an example sentence, collocations including "make every endeavour" and "endeavour to understand," synonym pairs like attempt and effort, and a flashcard prompt for later review.
• Selective dictionary building. Suggested words surface in results but enter the personal dictionary only after explicit confirmation, which keeps the vocabulary list tied to what the learner genuinely wants to study.
• Long-form checking inside the account. The public landing form accepts 30 to 300 characters, while the checker available after sign-in processes texts of up to 5,000 characters, covering emails, work notes, and short essays.
• Chrome extension for in-page capture and review. A highlighted word can be saved with a single click while browsing, and a second mode checks writing directly in a popup that returns corrected text with grammar notes.

How It Works

A visitor pastes English text into the landing form, which accepts between 30 and 300 characters. Pressing the check button opens a Google sign-in window if the session is unauthenticated, and the draft remains in the browser tab until submission. After sign-in and selection of a native language, the text is transmitted to OpenAI for analysis and the result opens inside the account. Output combines a correction, an explanation of the rule, and a vocabulary suggestion. Both the submitted text and the result are stored on the account, a detail documented in the privacy policy.

Who It's For

The tool suits intermediate learners who can read and write English but keep repeating predictable mistakes, particularly Russian speakers, since the interface, sample sentences, and word translations cover English and Russian. It also fits professionals who write work emails and messages daily and want corrections explained rather than applied automatically, along with students preparing for exams who need drills generated from their own writing instead of generic textbook exercises.