TaskUse console.time('compute') + console.timeEnd('compute') around a small loop (sum 1..1000). Then console.warn('careful') and console.error('boom'). Finally console.table([{a:1,b:2},{a:3,b:4}]).
console beyond .log — group, table, time, trace
100 XP7 min
Theory
You're using 1/5 of console
console.log is the workhorse but the other methods solve real debugging problems.
console.table
Renders an array of objects as a real table. Sortable in devtools.
const users = [{ id: 1, name: "Anna" }, { id: 2, name: "Bob" }];
console.table(users);console.group / groupEnd
Collapsible sections in devtools. Best for nested operations.
console.group("loadDashboard");
console.log("step 1");
console.log("step 2");
console.groupEnd();console.time / timeEnd
Measures elapsed time. Pair with the same label.
console.time("parse");
const data = JSON.parse(huge);
console.timeEnd("parse"); // parse: 4.3msconsole.trace
Logs a stack trace from the current call site. Find "who called this".
console.warn / error
Same as log but devtools colors them yellow/red. Filter by level.
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