Drawing Grid Overlay Tool

How to use the drawing grid overlay tool

1. Choose an image or drop it on the box. JPG, PNG, WebP, GIF, BMP and AVIF files up to 25 MB are accepted.
2. Set the squares by size in pixels or by columns across, then choose the line width, color and strength.
3. Turn on Label columns and rows to letter the columns and number the rows.
4. Press Download PNG. The saved picture has the same pixel size as your original.

How the grid is placed

The grid method is a drawing technique where you copy a picture one square at a time. The grid is drawn at every multiple of the square size, and only inside the picture. An 800 by 600 image with 100 pixel squares has 8 columns and 6 rows, with 7 vertical and 5 horizontal lines. If the square size does not divide the picture evenly, the squares along the right and bottom edges are partial. A 150 pixel grid on the same image has 6 columns and 4 rows, with the last column and row cut short.

When you set the grid by columns across, the square size is the image width divided by the number of columns, so 8 columns across an 800 pixel image gives 100 pixel squares. Squares smaller than 4 pixels, or more than 200 squares in a row or column, are refused so the grid stays usable.

Using the labels and the saved picture

With labels on, columns are lettered A, B, C and so on, then AA, AB after Z, and rows are numbered from 1. Draw a matching grid lightly on your paper with the same number of squares and copy what you see in each square of the picture into the matching square of the drawing. Use a light line color and a thin line for a faint guide, and a bold color on a dark photo.

The preview is scaled to fit your screen, and the saved PNG is drawn at the full size of the original. To split a picture into separate tiles instead, use the Image Splitter Grid. The Graph Paper Generator prints the paper to draw on, and the Poster Printer and Tiler spreads a large picture over several sheets. The Add Border to Image tool frames the result.

Assumptions and limits

• The image is changed in your browser and is never uploaded.
• The first bytes of the file are checked, and SVG or unknown types are refused.
• Line positions are rounded to whole pixels, so a fractional square size can shift a line by up to half a pixel.
• Photos from phones that store a rotation are shown upright. Camera and location data is not copied to the new file.

Formulas reviewed October 10, 2026. See the calculation methodology for how SumPanda rounds, tests and sources its formulas.

Frequently asked questions