EBay SEO That Increases Best Match RankingsProfessional Cassini optimization for higher visibility and conversions

eBay's Cassini search algorithm represents one of the most sophisticated e-commerce ranking systems, using machine learning to evaluate hundreds of signals across listing quality, seller performance, and buyer behavior. Understanding Cassini's core principles separates consistently successful sellers from those struggling with visibility.

Cassini prioritizes relevance above all else, measuring how well listings match buyer intent through engagement signals like click-through rate, conversion rate, and time-on-page. The algorithm actively demotes listings that receive impressions but fail to generate engagement, interpreting this as poor relevance. This creates a feedback loop where well-optimized listings gain progressively more visibility while underperforming listings fade into obscurity.

The algorithm evaluates seller authority at the account level, not just individual listings. Your entire catalog's quality, your performance metrics, your category specialization, and your sales velocity all contribute to a domain authority score that amplifies or suppresses individual listing performance. New sellers face an initial trust deficit that only consistent sales and positive feedback can overcome.

Cassini's real-time nature means rankings fluctuate constantly based on recent performance. A listing generating strong sales today may see improved placement tomorrow, while yesterday's top performer can drop quickly if engagement declines. This dynamic environment rewards sellers who continuously monitor performance and adjust strategies based on data rather than assumptions.

Understanding these foundational principles allows sellers to align their optimization efforts with how Cassini actually evaluates and ranks listings, rather than chasing outdated tactics that no longer influence modern algorithmic decisions.

eBay titles represent the single most important on-page SEO element, with your 80-character limit requiring strategic decisions about what information to include. Cassini weighs title keywords heavily when matching listings to search queries, but title construction has evolved far beyond simple keyword placement.

Front-load your most important keywords in the first 40 characters since these appear in mobile truncated views and carry more algorithmic weight. Start with your primary keyword or brand name, followed by model number, key attributes, and secondary descriptors. Every character must justify its presence by either matching common search queries or differentiating your listing from competitors.

Avoid keyword stuffing, special characters (!!!, ****, +++), promotional language (WOW, L@@K, SALE), or irrelevant brand names. Cassini actively penalizes these practices as manipulation attempts. Instead, focus on semantic relevance by including terms buyers actually search for when looking for your specific product.

Include critical attributes that buyers filter by: size, color, material, condition, compatibility, or capacity. A laptop listing should specify screen size, processor, RAM, and storage in the title because buyers search using these specifics. Generic titles without distinguishing details blend into search results and fail to capture qualified traffic.

Test title variations systematically by monitoring impression and click-through rate changes after modifications. Sometimes small adjustments — reordering keywords, adding a specific attribute, or removing redundant terms — can significantly impact visibility. Title optimization is an ongoing process, not a one-time task.

Item specifics function as structured data that Cassini uses for precise relevance matching and category filtering. Incomplete or inaccurate item specifics can reduce visibility by 40-60% because Cassini cannot confidently match your listing to relevant search queries and filters.

Complete every available item specific field for your category — eBay provides 20-40+ category-dependent fields covering brand, model, size, color, condition details, materials, features, and technical specifications. Each completed field increases your listing's relevance score and qualifies it for more filtered search results where buyer intent is highest.

Accuracy matters as much as completeness. Incorrect item specifics trigger buyer complaints and returns, which directly harm your seller performance metrics and suppress future visibility. Verify specifications against manufacturer documentation rather than guessing or copying potentially incorrect competitor data.

Custom item specifics allow you to add attributes beyond standard fields, useful for niche products with specialized characteristics. Use these strategically for differentiating features that buyers in your category specifically seek but that aren't captured by standard fields.

Cassini uses item specifics for semantic understanding of your product, connecting it to related searches even when exact title keywords don't match. A dress listed with 'floral' pattern specifics may appear in searches for 'flower dress' or 'botanical print dress' through Cassini's semantic associations, expanding your potential visibility beyond literal title matches.

Choosing the correct primary and secondary categories directly affects which searches display your listings and how Cassini evaluates relevance within competitive contexts. Category misplacement can reduce visibility by 50-70% by putting you in front of the wrong buyer audience or in inappropriately competitive environments.

eBay's category structure includes over 20,000 leaf categories, and finding the most specific relevant category improves rankings. A vintage Rolex belongs in 'Jewelry & Watches > Watches, Parts & Accessories > Watches > Wristwatches' rather than the broader 'Jewelry & Watches' parent category. Specific placement signals expertise and matches buyer navigation patterns more precisely.

Utilize secondary categories strategically for products that legitimately fit multiple classifications. A vintage band t-shirt could list in both 'Clothing' and 'Entertainment Memorabilia > Music Memorabilia,' capturing buyers searching different category trees for the same item. This doubles your category-specific visibility without diluting relevance.

Category choice affects competitive intensity and Cassini's baseline expectations. Electronics categories with thousands of identical listings require aggressive pricing and perfect optimization, while niche collectibles categories with fewer listings allow more pricing flexibility but demand precise relevance to specialized buyer intent.

Monitor eBay's category changes quarterly, as the platform regularly restructures and adds categories to improve buyer navigation. Listings remaining in deprecated or restructured categories may lose visibility as buyer traffic shifts to new category paths. Proactive category updates maintain optimal positioning.

eBay descriptions serve dual purposes: converting visitors who clicked your listing and providing search engines with indexable content for external SEO. While Cassini doesn't heavily weight description text for internal rankings, descriptions directly impact conversion rates, which Cassini monitors closely as a relevance signal.

Structure descriptions with scannable formatting using headers, bullet points, and white space. Mobile buyers dominate eBay traffic, and dense text blocks are unreadable on small screens. Present the most critical information — condition details, specifications, shipping terms, and return policy — in the first 300 words before requiring buyers to scroll.

Include comprehensive product details that answer buyer questions preemptively: dimensions, weight, materials, compatibility information, what's included, condition explanations, and usage instructions. Each answered question reduces buyer hesitation and message volume while increasing conversion probability.

Natural keyword integration for Google SEO helps external search engines understand and rank your listings. eBay pages can rank in Google for commercial queries, capturing buyers who search outside eBay's platform. Include conversational keyword phrases in descriptions that match how people search Google differently than eBay's internal search.

Avoid excessive promotional language, all-caps sections, or misleading claims that trigger buyer complaints. Descriptions should build trust through detailed accuracy rather than hype. High-quality descriptions reduce return rates by setting accurate expectations, protecting the seller metrics that preserve your Cassini rankings.

Cassini includes price competitiveness as a ranking signal, comparing your listing price to similar items in your category. Significantly overpriced listings receive suppressed visibility because Cassini predicts poor conversion probability, while competitively priced items gain algorithmic favor through predicted relevance.

Research your category's price distribution using eBay's completed listings and Terapeak analytics. Identify the median price for items matching your product's condition, features, and brand. Pricing within 10-15% of this median balances competitiveness with profitability, while pricing 20%+ above median triggers visibility penalties.

Dynamic pricing adjustments based on market conditions, seasonal demand, and competitive landscape maintain optimal visibility. During high-demand periods, you can price higher without algorithmic penalty because the market median shifts upward. During slow periods, price reductions may be necessary to maintain competitive positioning.

Best Offer functionality provides pricing flexibility without committing to a fixed price. Enable Best Offer with automatic acceptance thresholds to test price sensitivity while maintaining higher list prices. Successful offers count as conversions that boost your Cassini rankings while allowing price optimization through real buyer feedback.

Promotional tools like markdowns and sales events temporarily increase visibility through dedicated promotional placements while also improving price competitiveness scores. Strategic promotion timing — launching during high-traffic periods or when organic rankings need a boost — maximizes the compounding visibility effects of both promotional placement and improved conversion signals.