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; const 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
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
textBaseline | Chrome Full support Yes | Edge Full support 12 | Firefox Full support 3.5 | IE Full support 9 | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support 4 | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
See also
- The interface defining this property:
CanvasRenderingContext2D