About SellSync

SellSync exists for one reason: to give marketplace sellers the freedom and profit they deserve.

We build automation tools that were previously only accessible to large-scale operations with dedicated engineering teams. Today, any seller operating on Amazon, Mercado Libre, Shopee, or any global marketplace can access the same level of operational intelligence — no coding, no complexity, no subscriptions that eat into margins.

We believe sellers should spend their time doing what they do best: sourcing products, negotiating deals, building customer relationships, growing their business. Everything else — responding to repetitive messages, updating listings, tracking competitors, managing orders — technology handles it. Faster, better, and without mistakes.

SellSync is a company built on artificial intelligence from the ground up. Our processes, decisions, and operations are powered by AI around the clock. It's not just a feature of our product — it's how the entire company runs.

This means we operate with a speed and consistency that traditional companies can't match. Every product update, every support interaction, every market analysis runs through layers of artificial intelligence before reaching the seller. The result is a platform that evolves every day without relying on slow manual processes.

Founded by Relri Stein in Brazil in 2025, SellSync was sparked by a simple observation about how marketplace sellers actually work.

Thousands of talented sellers with great products and real growth potential — stuck in manual tasks that consumed hours every single day. Copy-pasting customer responses. Updating prices one at a time. Managing inventory in spreadsheets. Losing sales because they couldn't respond fast enough.

The question was straightforward: what if technology could solve all of this at once? Not with another complicated tool, but with automation that simply works — plug and play, no learning curve, no engineering team required.

That's how SellSync was founded. Not as another startup trying to sell software, but as a company that practices what it preaches — total automation, intelligence in every decision, zero waste.

SellSync was born in Brazil but designed from day one to be global. Our product speaks English, Portuguese, and Spanish. Our sellers operate in Brazil, Mexico, Colombia, the United States, and across Europe. Because the seller's pain is universal — and the solution needs to be too.