is-symbol
Determine if a value is an ES6 Symbol or not.
npm says
129,004,826
per week
Every tarball fetch: mirrors, scanners, CI and people.
real installs
high confidence≈ 129M
per week
Mirror spikes and crawlers removed. CI and dependency installs still count, so this is not a head count.
noise under 1% of npm's count, so nearly all of it counts. noise real installs
Why this estimate
With JavaScript on, this lists what the filter found for this package.
Snapshot from the daily build of Nov 10, 2026, last 7 days of npm data. With JavaScript on, this page recomputes it live from the npm API.
How many people use is-symbol?
npm counted 129,004,826 downloads of is-symbol in the last 7 days. Nobody can count people exactly, npm included: it does not record who downloaded what. After removing mirror spikes and crawlers, about 129M look like real installs. At this scale most of them come from CI, builds and other packages that depend on is-symbol, so the number of people behind them is far smaller.
Is is-symbol still maintained?
Probably not actively: there has been no release in over a year, though that can also mean it is simply finished. The latest version, 1.1.1, came out on Dec 13, 2024. There were no stable releases in the last 12 months. It was first published on Jan 24, 2015. npm lists 1 maintainer.
Is is-symbol still used?
Downloads with publish spikes removed are up 47% over 3 months and up 147% over 11 months. For scale, the median of the 384 packages we track, which lean towards today's most downloaded, is up 164% over 11 months, so this one is behind that. Last week, 100% of downloads above the crawler floor were on major version 1, the latest one; the most used single version was 1.1.1, with 87%. Weekdays get 1.6× the downloads of weekends, which fits people at work, though CI follows the same rhythm. Crawlers account for about 1,029,903 downloads a week, roughly 147,129 per version.
Monthly downloads of is-symbol
The busiest month was Oct 2026, with about 16,724,197 downloads a day once publish spikes are removed; the quietest was Dec 2025 (the holiday season), with about 6,296,801.
| month | npm downloads | publish spikes removed | real installs | vs month before |
|---|---|---|---|---|
| Oct 2026 | 434,829,123 | 0 | 435M | up 14% |
| Sep 2026 | 396,705,728 | 0 | 397M | up 19% |
| Aug 2026 | 382,722,079 | 0 | 383M | up 5% |
| Jul 2026 | 363,244,900 | 0 | 363M | up 9% |
| Jun 2026 | 323,740,078 | 0 | 324M | up 11% |
| May 2026 | 302,013,262 | 0 | 302M | about flat |
| Apr 2026 | 285,778,588 | 0 | 286M | about flat |
| Mar 2026 | 290,608,042 | 0 | 291M | up 15% |
| Feb 2026 | 228,499,446 | 0 | 228M | up 17% |
| Jan 2026 | 216,697,962 | 0 | 217M | up 11% |
| Dec 2025 | 195,200,835 | 0 | 195M | — |
Whole months through Oct 31, 2026. Publish spikes are found day by day and summed per month. Real installs apply this week's crawler share to each month's downloads (the upper end also keeps the removed spikes), so they follow npm's curve rather than measure it. The change compares spike-free downloads per day.
Where do the downloads of is-symbol come from?
Probably mostly through other packages. Each package below requires the one above it, and their weekly downloads on the matching versions line up within about 30%. This is an inference from download counts, not something npm records.
- is-symbol 1.1.1 129M a week
- which-boxed-primitive 1.1.1 126M a week
Past which-boxed-primitive the trail splits or we can't follow it. These are still real installs, but the people running them may never have chosen is-symbol. How a package ends up like this.
How the estimate works
- Cut the spike every new version gets from mirrors in its first days.
- Subtract the flat floor robots download from every version each week.
- Show what is left as a range, with a confidence level. It still includes CI and dependency installs, so it is not a count of people.