What you can upload for an essay
Updated 19 September 2026
What happens to each kind of file
- Photos: JPEG, PNG, WebP, GIF, HEIC, HEIF
- Rotated upright and re-encoded to JPEG in your browser before anything is sent, which is what makes an iPhone HEIC work and what keeps a 12-megapixel photo to a sensible size. Read as pages.
- Rendered to page images in your browser, then read as pages. One PDF is one student.
- Word and rich text: .doc, .docx, .rtf
- Sent to be converted to plain text, then read as text. Needs you to be signed in.
- Plain text: .txt, .md
- Read straight in your browser, so it never makes the round trip at all.
- A Google Docs link
- Fetched as plain text using Google’s own export, which is why the sharing setting matters. Read as text.
- Typed or pasted text
- Read as text, up to 120,000 characters.
Why pages and text bill differently
A photographed or PDF essay is charged by its page count. A typed submission has no pages to count, so it is charged by length instead, at one item per 500 words, which is what a typed page actually holds. Whichever of the two is greater is what you pay, so a long typed essay costs more than a short one and a handwritten essay costs what its pages cost.
It is stated on the grading screen itself, under the button, in the same numbers. If you want the arithmetic in full, the How are pages counted answer on the FAQ works through the cases.
If a Google Docs link is refused
There are three distinct messages, and each one means something different. That doesn’t look like a Google Docs link means the URL is not a Google document at all. That Google Doc isn’t shared. Set it to Anyone with the link, Viewer, then paste the link again means the document exists but is private, which is the common one. And That Google Doc looks empty means it was read and there was nothing in it, which usually means the wrong document.
What this will not do
A private Google Doc cannot be read, and no permission prompt will appear. The link has to be set to Anyone with the link, Viewer. There is no Google sign-in step in this flow, so a doc left private simply comes back as not shared.
Screenshots and shrunken copies of handwriting are refused. Below roughly 1000 pixels on the long edge the writing is not reliably legible, and guessing at it is the failure mode worth avoiding. Send the original photo.
Pages, Open Document and Google Slides files are not accepted. The list above is the whole list. Export to PDF or Word first, which every one of those can do.
Converting a document needs you to be signed in. Word, RTF and Google Docs links are converted on our side, and that step requires an account. Plain text is read in your browser and never leaves it until you grade.
It reads the writing, not the layout. What comes back is scored against your rubric with notes pinned to sentences. Tracked changes, comments already in the document, and formatting are not part of what is graded.
Common questions
What file types does the essay grader accept?
Photos (JPEG, PNG, WebP, GIF, and HEIC or HEIF straight off an iPhone), PDF, Word documents (.doc and .docx), rich text (.rtf), plain text (.txt and .md), and a pasted Google Docs link. Anything else is refused with: Unsupported file. Use a photo, PDF, Word doc, or text file.
My Google Docs link will not work. Why?
Almost always sharing. A Google Doc that is private returns Google’s sign-in page rather than the text, and the grader reads that as not shared and tells you so: That Google Doc isn’t shared. Set it to Anyone with the link, Viewer, then paste the link again. Do that in the Share dialog of the document and paste the link once more. If the doc is empty you get a different message saying so.
Does a HEIC photo from an iPhone work?
Yes. It is converted to JPEG in your browser before anything is sent, which is also what shrinks a very large photo to a sensible size. The grading service itself only ever receives JPEG, PNG, WebP or GIF.
One of my photos was rejected as too small. What does that mean?
Handwriting needs roughly 1000 pixels on the long edge to be read reliably, and a photo under that is refused before it is graded rather than guessed at. The message names the page and its actual size. It is usually a screenshot, a photo saved from a messaging app, or a shrunken copy, so upload the original photo instead. Because the check happens before grading, a rejected photo costs you nothing.
Can I paste the essay text instead of uploading anything?
Yes, and it is the most reliable route for typed work. Pasted text is capped at 120,000 characters, which is far longer than any student essay.
Can one file hold the whole class?
No. One file is one student’s essay. A PDF holding a whole class is refused by name rather than partly graded, which has its own page.
How many essays can I upload at once?
Thirty in one batch. Adding more says so rather than quietly dropping them: That’s the limit for one batch (30 essays). Grade these first.
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