How to Check OMR Sheets With a Mobile Phone

Checking 60 OMR sheets by hand can take an entire evening. With the free ToolAdda OMR checker, your phone does the work in a few minutes. This guide explains the complete process and how to get reliable results.

Works with ToolAdda OMR sheets. The checker reads sheets created with the ToolAdda OMR sheet generator, because it uses their corner squares and QR code to find every bubble.

Step 1: Set the layout

You usually don't need to do anything: the checker reads the layout from the QR code on the first sheet. You can also:

press Check sheets in the generator, which opens the checker with your design and answer key;
press Use my generator design in the checker;
open a saved template file; or
scan the sheet's QR code with your phone's camera app, which opens the checker with that layout.

Then check the marking scheme: marks for correct and wrong answers in each section, and whether multiple marks count as wrong.

Step 2: Enter the answer key

Choose whichever is fastest:

Click the correct option for each question.
Paste the key as text, such as ABCDABCD… or 1-A, 2-C, 3-B.
Scan a key sheet: print an answer-key page from the generator (or fill a blank sheet with the correct answers) and add it like any other sheet. Key pages are recognised automatically.

If your test has booklet sets, enter a key for each set. The checker reads each student's set and uses the right key.

Step 3: Capture the sheets

With the live camera

Tap Use camera and allow camera access.
Place a sheet flat on a table and hold the phone above it so the whole sheet fills the frame.
When all four corner squares are found, the frame turns green and the sheet is captured automatically.
Replace the sheet with the next one. The checker pauses briefly between captures.

With photos or a scanner

Take photos with your camera app, or scan the sheets on a flatbed or document scanner at 150 to 300 DPI, then press Choose files or drag the files into the checker. Multi-page PDFs from a scanner are split into sheets automatically.

Tips for perfect photos

Do	Avoid
Even daylight or bright room light	Harsh shadows from your hand or phone
Sheet flat on a darker surface	Curled, folded or crumpled sheets
All four corner squares visible with a little margin	Cutting off corners or edges
Phone roughly parallel to the paper	Very steep angles
Steady hands, sharp focus	Motion blur and digital zoom

Rotated, upside-down and slightly tilted photos are corrected automatically.

Step 4: Review the results

Each sheet appears in the results table with its roll number, set, score, percentage and a status:

OK: read and scored without issues.
Check: something needs your attention, such as multiple marks, an incomplete roll number, a missing set code or a missing page.
Error or Other layout: the sheet couldn't be read or belongs to a different design.

Press View to open a sheet. Detected marks are circled in blue, and the correct answers are circled green (right) or red (wrong). If a mark was read incorrectly, choose the right response in the table and the score updates immediately.

Press Download CSV to save every student's roll number, set, section scores, total, percentage and individual responses. The file opens in Excel, Google Sheets or LibreOffice for ranking, analysis and report cards. Print produces a clean results table.

Troubleshooting

"Couldn't find the four black corner squares"

Make sure every corner square is inside the photo and not covered by fingers, staples or shadows. Use a darker background around the sheet.

"Couldn't read the QR code"

Move closer or improve focus. Once one sheet has been read, later sheets use that layout even if their QR code can't be read.

A light mark wasn't detected

Very faint pencil marks can be missed. Open the sheet and correct the response, and ask students to darken bubbles fully next time.

Privacy

Photos, answer keys and results are processed on your device and never uploaded. Download the CSV before closing the page, because results aren't stored.