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console.debug()

The console.debug() method outputs a message to the web console at the "debug" log level. The message is only displayed to the user if the console is configured to display debug output. In most cases, the log level is configured within the console UI. This log level might correspond to the `Debug` or `Verbose` log level.

Note: This feature is available in Web Workers

Syntax

debug(obj1)
debug(obj1, /* ..., */ objN)
debug(msg)
debug(msg, subst1, /* ..., */ substN])

Parameters

obj1 ... objN

A list of JavaScript objects to output. The string representations of each of these objects are appended together in the order listed and output to the console.

msg

A JavaScript string containing zero or more substitution strings, which are replaced with subst1 through substN in consecutive order.

subst1 ... substN

JavaScript objects with which to replace substitution strings within msg. This gives you additional control over the format of the output. See Using string substitutions in console for a description of how substitutions work.

See Outputting text to the console in the documentation of the console object for details.

Specifications

Specification
Console Standard
# debug

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
debug
1
12
4
10
11
4
≤37
18
4
11
3.2
1.0
substitution_strings
1
In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer. For example, -0.1 becomes -1.
12
["Before Edge 79, %c is not supported.", "Before Edge 79, %d outputs a 0 if the specified value isn't a number."]
9
10
[" %c is not supported.", " %d outputs a 0 if the specified value isn't a number."]
15
4
≤37
In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer. For example, -0.1 becomes -1.
18
In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer. For example, -0.1 becomes -1.
9
14
3.2
1.0
In Samsung Internet 1.5, if a negative value is passed to %d, it will be rounded down to the closest negative integer. For example, -0.1 becomes -1.

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https://developer.mozilla.org/en-US/docs/Web/API/console/debug