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How to draw straight lines freehand

Don’t mistake curves with wiggles. Connecting two dots creates a line. See how curved it is and how much it wiggles. Free to take, scored in your browser.

Straight line between two pointsYour turn
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The technique

Draw a straighter line freehand

4 steps
  1. 01

    Fix both ends first

    When following a line look at the starting dot, then the far dot, then come back to the starting dot. Your eye should trace the whole line before your hand starts to draw.

  2. 02

    Ghost the movement

    Practice the line two or three times above the paper at the same speed as you want to travel with the line.

  3. 03

    Watch the target, not the tip

    Try keeping your eye on the far dot while you draw. You have already rehearsed the path, so this gives the movement a clear destination without constantly correcting the pencil’s position.

  4. 04

    One pass, under a second

    Draw it in one continuous stroke without patching the line. Look at the result afterwards, then use the feedback to plan your next attempt.

How it works

What it can name

The faults, drawn

These percentages can mean nothing by themselves. Instead, each problem has its own fix. The examples below are all real strokes that I generated with the same code that I used to test the engine.

  • Bow

    The line bows into a smooth curve. Rehearse the straight route between the dots before the next pass.

  • Tremor

    Small waviness remains along the line after its broad curve is accounted for. Try a steady pace you can control.

  • Ratcheting

    The stroke has repeated short stops. Rehearse the route, then try one continuous movement between the dots.

  • Sideways miss

    The line is fairly straight but misses the intended route between the dots. Check both endpoints before drawing again.

  • Overshoot

    The stroke goes past the far dot. Plan the stopping point as well as the direction.

  • Stopped short

    The stroke stops short of the far dot. Rehearse the full distance and aim to finish on it.

How the number is made

What the score actually measures

Straightness

peak of fitted parabola23% of the score

The single smooth curve in your line. It is measured against the chord between your stroke’s own endpoints, so starting off target does not also count as curvature.

Steadiness

rms( d − parabola )19% of the score

The measurement after the main curve has been subtracted out. It helps tell a smoothly bowed line from a wavy line. Each may benefit from a different practice approach.

Aim

max |d| at either end25% of the score

How far sideways you landed from the target dots. Running past the far dot is measured separately from landing to one side.

Starting

|t_start|5% of the score

Where you began along the target line: before the start dot, on it, or beyond it. The far end is reported separately, so you can work on starting and stopping as different actions.

Stopping

|t_end − 1|7% of the score

How far past the end dot did you draw and how far short did you stop of the end dot?

Hesitations

stops over 8, or the fraction of the drawing spent stopped — whichever is worse9% of the score

How often the pen paused, and for how long. A single long stop is read as the share of drawing time spent still, while repeated short stops are counted. A change of direction is not automatically a pause.

One motion

how many extra strokes lie on the line6% of the score

Whether the line took one stroke. A reinforcing pass or false start along the same intended line can still be graded, using your last full stroke for the shape measures, but extra strokes count here. Unrelated strokes that do not form one line are rejected. A single stroke has no extra-stroke penalty.

One pass

furthest the pen fell back from its own high-water mark6% of the score

Whether you went back over the line within the same stroke. A line can reach the far dot, run back along itself and come forward again without changing its outline much. This measure catches that retracing even though you never lifted the pen.

Placement is measured against the two target dots. Curvature and steadiness are measured from the stroke itself, so a straight line in the wrong place still loses points for placement. Errors are scaled by the distance between the target dots. That makes the units comparable across canvas sizes, though different devices can still affect your results. Every threshold, and the evidence behind it.

A bowed line and a wavy line need different checks

A bow and a wobble can both look like a line that is not straight enough. Slowing down is an understandable response, but it may add more small corrections. First look at which kind of deviation the feedback found.

A smoothly bowed line can happen even when the movement felt steady. Rehearse a path between the two dots and look toward the far one as you draw. If the line keeps bowing the same way, try a more comfortable direction or position. The curve alone cannot tell us how your arm moved.

Repeatedly steering and correcting a line can add small wobbles. If that describes how you drew it, try a slightly brisker, rehearsed stroke. The first attempts may land less accurately. Device capture can affect the line too, so a wobble does not prove you drew too slowly.

Drawing the line in short pushes can leave small changes of direction at the joins. For this exercise, try one continuous stroke and leave it alone, even if it misses. That gives you a clearer attempt to learn from than repeatedly patching the same line.

Ghosting, which is the actual technique

For this drill, use three actions. First, locate the two endpoints. Then practise the motion above the surface at the speed you intend to draw. Finally, draw it in one stroke without correcting.

The rehearsal is planning the line. The stroke is carrying it out. If you are still deciding where to go while drawing, you may keep steering and correcting. A miss can come from either planning or execution, so rehearse again and use the next attempt to see what helps.

When you have got it

Aim for five lines in a row scoring above 85 with no named fault, using a comfortable, brisk stroke. Then try a diagonal direction. On paper you can also practise eight lines fanning out from one point. Ellipses offer a different next challenge: keeping the movement smooth while the direction changes.

Questions

My lines curve. Am I just drawing too fast?

Not necessarily. A smooth bow is different from a line made wavy by repeated corrections. Rehearse a straighter path toward the far dot, then try it in one comfortable stroke. The bow alone does not establish that your speed was wrong.

What is the difference between a bow and a wobble here?

A bow is one smooth deviation, measured by fitting a parabola. The wobble is what remains after that fitted curve is subtracted. They score separately so you can see which feature needs attention; neither measure proves a particular cause.

Is it cheating to draw the line very fast?

No. A brisk, rehearsed stroke is part of this exercise, not cheating. But speed alone will not earn a good score: the drill also measures shape and placement, so a fast line that misses the dots still loses points.

Should I use my wrist, my elbow or my shoulder?

With a pen, try a relaxed wrist and enough arm movement to cover the distance comfortably. Larger lines may benefit from more arm movement; small lines can use the fingers. Avoid locking a joint or forcing a particular motion. With a mouse or trackpad, find a setup that lets you reach both dots without straining.

Why does overshooting score better than missing sideways?

Overshooting means you reached the right direction but continued too far along it. A sideways miss means the endpoint landed away from the target line. They are measured separately so you can practise stopping and aiming separately, although either result can have several causes.

Does this work with a mouse?

The same geometry is measured on a mouse, pen or trackpad. The device can still affect how you aim, stop and keep the line steady, and a trackpad may require repositioning. Compare your scores with earlier attempts on the same hardware.

Can I erase or start again?

You can erase unwanted ink; the engine measures the strokes that remain. For this exercise, try a fresh continuous stroke when you want to practise the movement again. Use Undo or clear the canvas to start over. Attempts are unlimited.

Is my drawing sent to an AI model?

No. The calculations run in JavaScript in your browser, using the recorded coordinates and timing. The same stroke and scoring settings give the same result. This exercise does not send the drawing to an AI model.

Next drill

Ellipse inside a plane

Draw one complete ellipse to fill the box. Make two full laps without lifting.

Draw ellipse inside a plane

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