About Username Inspector

What is Username Inspector?

Username Inspector is a free web-based tool that checks username availability across multiple online selling platforms simultaneously. Launched in February 2026, the tool currently supports 11 platforms: eBay, Poshmark, Depop, Etsy, Grailed, Vinted, Mercari, Whatnot, Bonanza, Ruby Lane, and Chairish.

Unlike general username checkers that focus on social media platforms (Twitter, Instagram, TikTok), Username Inspector specializes specifically in e-commerce and reselling platforms where brand consistency is important for sellers.

Key Features

• Real-time auto-check mode: Live availability results (✓ available, ✗ taken) in seconds, no tabs to open — supports up to 5 usernames on eBay, eBay Store, Poshmark, Grailed, Vinted, Whatnot, Bonanza, and Chairish
• Multi-platform checking: Check username availability across 11+ platforms at once
• Bulk username checking: Enter up to 500 usernames in manual mode
• Direct profile links: Generate direct links to user profile pages for each platform
• No registration: No account, sign-up, or login required
• Completely free: No costs, no trials, no hidden fees
• Privacy-focused: No usernames are stored, logged, or tracked

How It Works

Username Inspector offers two modes:

Auto-check mode (up to 5 usernames)

1. Select platforms and enter up to 5 usernames
2. Click Check Availability — a lightweight serverless function queries each platform's public profile page in real time. This runs server-side rather than in your browser, since a browser can't make these cross-origin requests directly.
3. Results appear instantly: ✓ green = available, ✗ red = taken, ? yellow = manual check required (Depop, Etsy, Mercari, Ruby Lane)

Manual mode (up to 500 usernames)

1. Select platforms and enter up to 500 usernames
2. Click Check Availability — the tool generates direct profile URLs (e.g., ebay.com/usr/username) for every username/platform combination, entirely in your browser
3. Open and verify: Click each link or use Open All Tabs; "user not found" = available, active profile = taken

Auto-check requests pass through a stateless serverless function to get a real-time result; manual mode never leaves your browser. Either way, the usernames you check are never logged or stored.

Supported Platforms

Username Inspector currently supports 11 selling platforms:

• eBay (ebay.com) - Global online marketplace
• Poshmark (poshmark.com) - Fashion resale marketplace
• Depop (depop.com) - Youth-focused fashion marketplace
• Etsy (etsy.com) - Handmade and vintage marketplace
• Grailed (grailed.com) - Men's fashion marketplace
• Vinted (vinted.com) - Secondhand fashion marketplace
• Mercari (mercari.com) - General marketplace
• Whatnot (whatnot.com) - Live selling marketplace
• Bonanza (bonanza.com) - Online marketplace for unique items
• Ruby Lane (rubylane.com) - Antiques and collectibles marketplace
• Chairish (chairish.com) - Vintage and luxury furniture marketplace

Additional platforms are added regularly based on user requests and demand.

Who Uses Username Inspector?

Username Inspector is particularly useful for:

• Resellers: Setting up accounts on multiple platforms (eBay, Poshmark, Depop)
• Small business owners: Establishing brand consistency across selling channels
• Side hustlers: Launching multi-platform selling operations
• Vintage sellers: Checking availability on specialized platforms (Grailed, Vinted)
• Handmade sellers: Verifying Etsy username availability alongside other platforms
• Brand managers: Protecting brand names across e-commerce platforms

Why Brand Consistency Matters

Using the same username across multiple selling platforms provides several benefits:

• Customer recognition: Customers can easily find you on any platform
• Professional appearance: Consistent branding looks more established and trustworthy
• Cross-platform marketing: Easier to promote one username across all channels
• Search visibility: Consistent naming helps with search engine optimization
• Brand protection: Prevents others from using your name on different platforms
• Simplified promotion: One username to remember and share with customers

Privacy & Security

Username Inspector prioritizes user privacy:

• No data collection: Usernames you check are never stored, logged, or transmitted for tracking purposes
• Stateless checks: Auto-check requests pass through a serverless function to query platforms in real time and are discarded immediately after — nothing is retained
• No tracking cookies: We don't use cookies to track individual users
• No registration: No personal information is collected
• HTTPS encryption: All connections are encrypted via HTTPS
• Google Analytics: Only tracks page views and traffic sources (not individual searches)
• Open source approach: Simple, transparent code with no hidden functionality

Username Inspector vs. Alternatives

Username Inspector vs. Namechk

Namechk checks username availability across 500+ social media platforms (Twitter, Instagram, TikTok, etc.). Username Inspector focuses specifically on eBay, Poshmark, Depop, Etsy, Grailed, Vinted, Mercari, Whatnot, Bonanza, Ruby Lane, and Chairish - platforms used by resellers and online sellers. Username Inspector is more relevant for e-commerce sellers who need brand consistency across selling platforms rather than social media.

Username Inspector vs. KnowEm

KnowEm checks 500+ social networks and offers trademark search and brand protection services. Username Inspector checks only 11 platforms but focuses exclusively on the most popular selling platforms for resellers. Username Inspector is free and requires no registration, while KnowEm offers premium paid services.

Username Inspector vs. Manual Checking

Manually visiting each platform and searching for usernames takes 5-10 minutes per username. Username Inspector reduces this to seconds — auto-check mode returns a live available/taken result for eBay, eBay Store, Poshmark, Grailed, Vinted, Whatnot, Bonanza, and Chairish instead of just handing you a link to click through yourself. For users checking multiple usernames across multiple platforms, this represents a significant time savings.

Future Development

Potential features being considered:

• Additional platforms: Facebook Marketplace, OfferUp, Thredup
• Bulk export: Download results as CSV or PDF
• Username generator: Auto-suggest available usernames based on keywords
• Browser extension: Check usernames directly from browser toolbar
• API access: Developer API for integrating username checking into other tools

Feature development is driven by user feedback and demand.

Learn More

Visit our blog for guides on choosing a username, platform-specific username rules, cross-listing tools, and pricing across platforms. Need to compare fees? Try the fee calculator. Have questions? Check the FAQ.

Support & Contact

Username Inspector is supported by optional donations via Buy Me a Coffee. Donations help cover hosting costs and support continued development.

For feature requests, bug reports, or general inquiries, visit our Contact page.