How Mercari boosted seller confidence and drove millions more listings with Photoroom

Life before Photoroom

• Sellers struggled with listing due to messy or private backgrounds

• Casual sellers hesitant to photograph items in cluttered spaces

• iOS SDK and other third-party tools delivered poor quality product images

• Many listings abandoned, reducing marketplace supply

Life with Photoroom

• Simple automated background blur button increases seller confidence

• Millions of photos processed monthly with seamless API integration

• Increased number of listings by casual sellers and heavy users

• Projected 10% adoption, targeting 1% increase in marketplace listings (massive impact for Japan's dominant C2C marketplace)

Nick Pittoni has seen marketplace behaviors across continents—from the UK to Germany, Spain to the US. But nothing prepared him for the unspoken rules of selling in Japan.

As Product Lead for AI and LLM consumer applications at Mercari, Japan's dominant C2C marketplace, Nick discovered that Japanese sellers operate by a completely different playbook. "There's a high bar for sellers and buyers, and you're kind of expected to know what you're doing," he explains. "Otherwise you get penalized. You can get negative feedback fairly easily."

This cultural expectation creates a unique challenge: in a country where most of the population knows Mercari and many have accounts, the pressure to create perfect listings can actually prevent people from selling at all. And for a marketplace that thrives on fresh inventory, hesitant sellers translate directly to missed revenue opportunities.

When perfect becomes the enemy of good enough

Japan's marketplace culture demands authenticity at a level that would surprise most Western sellers. Japanese sellers meticulously document every scratch, stain, and imperfection with detailed photos and descriptions. “If you're buying a CD or a game, they would photograph the back at precisely the right angle to show buyers exactly how many scratches to expect,” shares Nick.

But this commitment to transparency created an unexpected bottleneck. Through regular user interviews, Nick's team discovered that several sellers were listing less frequently not because of the items themselves, but because of where they were taking the photos.

"Many sellers are often very conscious about where they're taking their photos. In Japan, more often than not, maybe the house is a bit small, the space is kind of cramped, and the background can be messy."

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

The result? Potential sellers would postpone or abandon their listings entirely rather than show a messy room or reveal their private spaces. For Mercari, this meant reduced marketplace liquidity and missed growth opportunities.

Nick had tried various solutions before, including a previous collaboration with Photoroom during its infancy. In recent years, his team explored iOS SDK tools, third-party models, and other AI tools, focusing on buyer experience and conversion.

But as Nick would realize, “The quality wasn't very good across the board, and we didn't see the conversion improve.” It became clear to Nick that they needed a solution that delivered accurate results and solved the real pains of sellers.

A single-button solution for sellers

When Nick's team reconnected with Photoroom years later, the technology had evolved significantly. More importantly, they’d learned to focus on the right problem: seller confidence rather than buyer conversion.

Integration with the Photoroom background removal API was simple.

• Implementation timeline: A small team of 3-4 engineers at Mercari brought the feature from initial discussion to production in 2-3 months.

• Solution focus: They prioritized the background blur feature to remove distractions from product photos while retaining the real life appearance of the product.

• Sellers new process: When Mercari sellers open the live camera to photograph an item, they click a single button and it instantly blurs their background.

"The Photoroom API was very easy to integrate with. Working with the Photoroom commercial and technical teams was smooth and straightforward, we got to production quickly with a small team.”

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

What impressed Nick most wasn't just the quality, but the scale Photoroom could handle. Mercari is a complex marketplace with billions of listings. Having Photoroom’s infrastructure on their side makes it easy to process millions of images, freeing their engineering team to focus on more strategic projects.

“Photoroom processes high single digit million images monthly for our sellers without slowing the listing experience.”

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

The expected and surprising results

The impact became clear almost immediately after launching the background blur feature.

Increased number of listings

Photoroom's background blur solved a distinctly human problem: the anxiety of sharing private spaces. By removing a psychological barrier that was preventing listings, Mercari unlocked millions of additional photos and measurably increased marketplace supply.

”After launching the ability to blur listings’ backgrounds, there was very significant boost in average number of items published by casual sellers, and a positive impact across all segments”

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

Expansive seller adoption

More intriguingly, the feature attracted unexpected users. While Nick's team hypothesized that casual, light sellers would be the primary adopters, "pro sellers or heavy sellers are adopting this feature a lot more than the light sellers," Nick shares. These experienced sellers, who presumably already had their own photo editing workflows, embraced the convenience of in-app background removal.

Ambitious adoption rate

Mercari is targeting more seller adoption of the background blur feature, which they estimate will increase overall marketplace listings by 1%.

“We can share indicatively that with an adoption rate of 10% of users, we are aiming to raise the amount of listings on the marketplace by 1%.”

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

For a startup, 1% might sound modest. But for a C2C environment at Mercari's scale, that translates to enormous business impact on GMV and revenue.

Improved sellers’ confidence

The feature means sellers can avoid worrying about where they list from. Oftentimes in Japan, young people may help older parents get rid of unwanted objects, but taking photos can be challenging in such locations. Whether it's the clutter or the old school looking floor, now they don't have to worry about it.

“Photoroom helps sellers build confidence to showcase the products they’re most passionate about. By boosting sellers' confidence when taking listing photos, anyone can list anything, anywhere, at any time.”

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

Looking ahead

While focused on maximizing adoption of the background blur feature, Nick's team continues exploring Photoroom as a visual partner.

"We are always exploring and staying in touch with the Photoroom team, learning about all the new features and testing them out. We tried one of the latest features recently to improve the lighting."

— Nick Pittoni, AI/LLM Consumer Product Lead at Mercari

The key, Nick emphasizes, is staying grounded in real sellers’ problems rather than getting swept up in AI capabilities, echoing a shared value with the Photoroom team. "With AI it's very easy to get excited and create new problems that maybe users don't have and bloat your product experience,” says Nick. “So sometimes it's just the simple things that make the overall experience better."