CanvasRenderingContext2D.textBaseline

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The CanvasRenderingContext2D.textBaseline property of the Canvas 2D API specifies the current text baseline used when drawing text.

Syntax

ctx.textBaseline = "top" || "hanging" || "middle" || "alphabetic" || "ideographic" || "bottom";

Options

Possible values:

"top"
The text baseline is the top of the em square.
"hanging"
The text baseline is the hanging baseline. (Used by Tibetan and other Indic scripts.)
"middle"
The text baseline is the middle of the em square.
"alphabetic"
The text baseline is the normal alphabetic baseline. Default value.
"ideographic"
The text baseline is the ideographic baseline; this is the bottom of the body of the characters, if the main body of characters protrudes beneath the alphabetic baseline. (Used by Chinese, Japanese, and Korean scripts.)
"bottom"
The text baseline is the bottom of the bounding box. This differs from the ideographic baseline in that the ideographic baseline doesn't consider descenders.

The default value is "alphabetic".

Examples

Comparison of property values

This example demonstrates the various textBaseline property values.

HTML

<canvas id="canvas" width="550" height="500"></canvas>

JavaScript

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');

const baselines = ['top', 'hanging', 'middle', 'alphabetic', 'ideographic', 'bottom'];
ctx.font = '36px serif';
ctx.strokeStyle = 'red';

baselines.forEach(function (baseline, index) {
  ctx.textBaseline = baseline;
  let y = 75 + index * 75;
  ctx.beginPath();
  ctx.moveTo(0, y + 0.5);
  ctx.lineTo(550, y + 0.5);
  ctx.stroke();
  ctx.fillText('Abcdefghijklmnop (' + baseline + ')', 0, y);
});

Result

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'CanvasRenderingContext2D.textBaseline' in that specification.
Living Standard  

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
textBaselineChrome Full support YesEdge Full support 12Firefox Full support 3.5IE Full support 9Opera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yes

Legend

Full support  
Full support

See also