Why OpenGrader
One rubric, one standard, the whole class
Pasting essays into a chat works until about essay 20, when the standard has quietly drifted and nothing can show you the class as a whole. OpenGrader is built for the batch.
The same standard, essay 1 to essay 30
Every submission gets its own isolated prompt against the same rubric. The bar does not shift as you get tired or as the pile grows.
In a chat, essay 25 is judged by a drifted standard you cannot see.
Every score cites the student’s own words
Each criterion has to come with a quoted or closely paraphrased line from that student, or an explicit "insufficient evidence". No score floats free of the text.
In a chat, "good structure, nice work" counts as an answer.
Genre-aware, on top of your rubric
Pick the writing type and it adds the right checks, like counterargument handling or textual citation, as separate feedback that never touches your rubric score.
In a chat, you re-explain the genre on every paste.
A cross-class consistency check
After grading, one more pass compares every result and flags pairs where the evidence looks about the same but the scores do not.
In a chat this is not possible. It only ever sees one essay.
About that API key
OpenGrader doesn’t sell you AI. You bring a key from Google, Anthropic, or OpenAI and the grading runs on your account. Google’s has a free tier that covers a class set; Claude or GPT run a few cents for the same pile. The key lives in this browser tab and goes straight to the provider with each request. We never see it, and there is no server keeping your students’ writing, because there is no server doing anything except handing the request along.
What it won’t do
- It’s not a plagiarism checker. It reads what’s in front of it and takes the text at face value.
- It doesn’t know your students. If Maria always buries her thesis in paragraph three, you know that and it doesn’t.
- It will miss things. The evidence line next to every score is there so you can check its work in about ten seconds a student.
- The grade is yours. Every number and comment is editable, and nothing leaves the page until you send it.
Your rubric. Your key. Your call on every grade.
It makes the first pass fast. It never takes the read away from you. Built for the stack of essays already on your desk.
Open the workspace