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A full list of JavaScript operators with examples

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Which is more popular?
Based on our record, JavaScript Operator Lookup seems to be more popular. It has been mentioned 1 time since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | joshwcomeau.com | sellwhere.app |
| Platforms | — | |
| Company | — | 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


No description of JavaScript Operator Lookup yet.
SellWhere is a free fee comparison tool built for resellers who sell across multiple platforms. One input, six answers. Enter a sale price once and instantly see your net payout ranked across eBay, Poshmark, Mercari, Vinted, Depop, and Etsy. No more switching between calculators or guessing which...
What each product offers, as listed by its team.


Possible disadvantages
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing JavaScript Operator Lookup and SellWhere.app.
SellWhere.app's answer:
SellWhere.app's answer:
SellWhere is the only free tool that lets you enter a sale price once and instantly compare your net payout across 6 major resale platforms — eBay, Poshmark, Mercari, Vinted, Depop, and Etsy. Most fee calculators only handle one platform at a time.
Our eBay calculator goes deeper than any competitor, modeling 20+ item categories, 6 store subscription tiers, and 3 seller levels. Every calculator shows when fees were last verified, with direct links to official fee pages so you can trust the numbers.
SellWhere.app's answer:
SellWhere serves two main groups:
SellWhere.app's answer:
SellWhere was born from a real frustration: resale platform fees are confusing, constantly changing, and scattered across different help pages. We wanted one place to see exactly what you'd take home on every major platform, with no guesswork.
Resale fees are also in a period of rapid change — Mercari dropped its seller fee to 0% in 2024, Depop eliminated buyer fees in mid-2024, and Vinted launched in the US in January 2026. Keeping up is hard. SellWhere was built to be the single source of truth for resellers navigating these shifts.
Share your experience with using JavaScript Operator Lookup and SellWhere.app. For example, how are they different and which one is better?
Recommendations tracked on public social media and blogs since March 2021.


If you replace your || with ?? You should get the behaviour you are after. This is a good reference for what the operators do in js: https://joshwcomeau.com/operator-lookup. Source: about 5 years ago
Tracking SellWhere.app since Aug 2026.
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