Lodash
The old standby for array/object helpers, still maintained, though check if native JS or a lighter alternative already covers what you need before adding it.
What is Lodash?
Lodash is a JavaScript utility library providing consistent, well-tested helper functions for arrays, objects, strings, and functions, things like deep cloning, debouncing, grouping, and deep equality checks. It predates a lot of what's now native to JavaScript (spread, Array.flat, optional chaining), so its usefulness today depends heavily on which specific functions a project actually needs.
Key features
- Broad coverage of array/object/collection helpers with consistent, well-documented behavior
- Deep clone, deep merge, and deep equality functions that are still genuinely awkward to write by hand in vanilla JS
- Debounce and throttle utilities that remain some of its most-used exports
- Modular imports (
lodash/get,lodash/debounce, etc.) so a bundler can tree-shake down to only what's used
Who it's for
Projects that need a handful of specific, well-tested utilities (debounce, deep clone, deep merge) without writing and testing them from scratch. Worth checking first whether native JS, a smaller focused package, or a couple of one-off functions already cover the need, since pulling in all of Lodash for one helper is unnecessary weight.
Pricing
Free and open source.