Drawing Checker for Artists: Reference Overlay

Workspace

Head Canon

Upload a sketch, study, or reference to inspect the drawing structure.

Horizon Center Left VP Right VP

Upload

Upload drawing or sketch

JPG, PNG, WebP

axis angle space

Top of skull Hairline Brow line Eye line Bottom of nose Bottom mouth Bottom of chin 1/3 1/3 1/3 1/3 2/3

Ref Drawing

Opacity Scale Move X Move Y Rotate

Vanishing Points

Perspective Check

1 VP

Horizon VP Center Left VP Right VP

Rays

Left spread Right spread Opacity

Mode One point

Horizon 48%

Check Edges to VP

Head Canon

3.5 Unit Overlay

Front

Size Move X Move Y Opacity

Body Canon

8 Head Overlay

Front

Size Move X Move Y Opacity

Reference vs Drawing

Layer Compare

Align

Upload both images, then align the drawing over the reference in the preview.

Upload Reference Upload Drawing

Drawing opacity Scale Move X Move Y Rotate

Drawing Read

Head Canon

Waiting

Structure Score

-- Upload a drawing to start.

Envelope --

Axis Drift --

Main Angle --

Big Shape Check

Envelope + Divisions

Envelope --

Center Pull --

Mass Split --

Proportions

Check the big height-width relationships and major shape divisions.

Angles

Compare the main tilts and directional lines before refining details.

Alignment

Use center axes and landmarks to see whether the drawing is drifting.

What To Fix First

The first fix will appear here after upload.

How to check a drawing against a reference

A small proportion error can carry through every layer of a painting. M8 Drawing Checker helps you compare a sketch with its reference and inspect the large relationships before refining details.

Choose Compare, then upload your reference and a photograph of your drawing. Use a straight-on photograph with even lighting to reduce camera distortion.

Use Scale, Move X, Move Y, and Rotate to align the same landmarks. Adjust drawing opacity or switch to Difference to compare the outlines.

Inspect the overall height and width, main angles, and negative spaces. For receding edges, switch to Perspective and place the horizon and vanishing points.

A studio example

For a portrait study, align the top of the skull and chin first. Lower the drawing opacity and compare the eye line, nose, and outer silhouette. If one feature drifts, check its distance from the center axis before correcting details.

What to keep in mind

Head and body canons are comparison guides, not rules for every person or pose. Perspective, camera angle, and intentional stylization affect the comparison. Upload and drawing checks require the full unlock shown in the tool.

Continue your painting study

Created by Jan Matěják (Jan Matejak), oil painter, teacher, and creator of M8 Painting Tools.