One form. Ten marketplaces. PostOnce formats your listing for eBay, Poshmark, Mercari, Facebook Marketplace, OfferUp, Etsy, Depop, Grailed, StockX, and Whatnot — including direct eBay posting via OAuth.
Get notified when new marketplaces launch:
How it works
No browser extensions. No desktop required. Just your listings, everywhere.
Upload photos, write your description, set your price. One form captures everything every marketplace needs.
eBay, Poshmark, Mercari, Facebook Marketplace, OfferUp, Etsy, Depop, Grailed, StockX, and Whatnot. Select which platforms to hit.
One click publishes your listing everywhere. Titles and tags auto-optimize for each platform's algorithm.
Enter details once. Get formatted, ready-to-post listings for every platform.
Authentic Levi's 501 in a classic stone wash finish. Size 32x30. Good pre-owned condition with natural fade and soft feel — ready for everyday wear or styled for any occasion.
The iconic Levi's 501 in stone wash — the jeans that never go out of style. Size 30 waist, 30 length. Light fading adds character. Perfect for layering or wearing solo. Ships same day!
Classic Levi's 501 straight leg jeans in stone wash. Size 30x30. Soft from wear, great color. True vintage piece. No returns — check measurements!
the one ☀️ vintage levis 501 in the perfect stone wash. w30 l30. super soft already, great everyday denim. authentic, no fakes!
Other tools depend on Chrome extensions that break every time a marketplace updates. PostOnce runs in the cloud. Works from any device, any browser.
Competitors cap you at 3 platforms per listing unless you pay more. PostOnce doesn't gate your reach behind add-on fees.
Connect your eBay account once and PostOnce posts listings directly via the official API — no copy-paste, no manual submission, no extensions.
What works on eBay doesn't work on Poshmark. PostOnce auto-adapts your titles, descriptions, and tags for each platform's search algorithm.
Beta testers report saving 2–3 hours per day on cross-listing.
"I was spending 45 minutes every morning listing the same items across four apps. PostOnce cut that to under 10 minutes. I actually have time to source now."
"Double-sold two items in one week before PostOnce. Hasn't happened since. The eBay direct posting was the feature I didn't know I needed."
"The Chrome extension I was using kept breaking every update. PostOnce just works — I've listed from my phone at the thrift store before I even drove home."
Other tools charge per marketplace, break with Chrome updates, or cap your reach. PostOnce doesn't.
| Feature | PostOnce | Vendoo | Crosslist |
|---|---|---|---|
| Marketplaces supported | 10 | 10 | 5 |
| No Chrome extension needed | ✓ | ✗ | ✗ |
| Direct eBay API posting | ✓ | ✗ | ✗ |
| StockX support | ✓ | ✗ | ✗ |
| Mobile-first (no desktop required) | ✓ | Partial | ✗ |
| Free to start | ✓ Free early access | $19/mo | $29/mo |
Connect your eBay account once via OAuth and PostOnce posts your listings directly — no copy-paste, no Chrome extension, no switching tabs.
Connect eBay & start listing →Free during early access · No credit card required
Every hour spent re-listing is an hour not spent sourcing, pricing, or shipping. Start free today — no waitlist.
Free during early access · Accounts & premium launching Summer 2026 · No credit card required
Guides and tips for resellers selling on eBay, Poshmark, and Mercari.
Stop manually re-typing listings. Post once, reach all three marketplaces.
Read guide → TipsA practical breakdown of each platform and how to manage all three without chaos.
Read guide → ComparisonPostOnce vs. Vendoo vs. Crosslist vs. List Perfectly — find the right tool for your operation.
Read comparison →