Last updated: 2026-07-11 · Applies to the Item Value Checker browser extension v0.1.0 and later.

Plain-English summary

The extension handles images you upload, paste, or right-click. It also runs default-on value-badge overlays on supported Facebook Marketplace, Craigslist, OfferUp, and Mercari pages. Those overlays read detected listing image URLs and visible listed prices and automatically process the detected cards. You can turn overlays off in the extension popup.

Right-click and overlay checks first send the raw image URL to the Item Value Checker backend. Uploads and pasted images send image bytes. If the URL-first route cannot process an image, the extension fetches and resizes it and sends base64-encoded image bytes instead. The backend may forward image bytes to eBay's image-search service. The extension does not request browsing-history or tabs permission, does not read login credentials, and does not collect unrelated page content.

What the extension does with data

Data	When collected	How used	Retained?
Listing image URLs	When you right-click an image or an enabled overlay detects a supported marketplace card	Posted as a raw `image_url` to our `/api/check-by-url` endpoint so the backend can fetch and process the image	The URL can appear in local recent history; a hash of it keys the 24-hour local result cache
Image bytes	When you upload or paste an image, use a data-URL image, or the URL-first route needs its fallback	Sent to our backend as base64; the backend may forward the bytes to eBay image search. Optional AI listing generation also sends the selected image to OpenAI after you request a draft	A pending right-click data image is held locally until the popup consumes it. The extension does not add raw image bytes to its result cache or history. Our application processes the bytes for the request and may cache the derived estimate, not the raw image; service providers process data under their policies
Visible listed prices	When an enabled overlay detects a supported marketplace card	Compared locally with the estimate to display a directional deal badge	Included in local recent history; not included as a field in the value-check request
Source page URL and hostname	After a successful automatic overlay check	Lets recent history link back to the supported marketplace listing or search page	Stored in local recent history; not included as a field in the value-check request
Results, recent history, and saved items	After a successful check or when you save an item	Displays prior estimates, supports saved items, and enables CSV export	Stored in `chrome.storage.local`. The result cache expires after 24 hours; recent history is capped at 50 and saved items at 100, and both can be cleared in the popup
Extension settings	When the popup loads or you change a setting	Keeps the overlay toggle (default on) and last listing-draft marketplace across browser sessions	Stored in `chrome.storage.sync` and handled by Chrome's sync service when sync is enabled
Technical request data	When an API request is made	Our infrastructure receives standard request information such as IP address and headers for delivery, quotas, security, and diagnostics	Handled under this policy, the main Item Value Checker privacy policy, and our infrastructure providers' policies

What the extension does NOT do

Request permission to read your general browsing history or open-tab list
Request cookie permission or read passwords, login forms, cookies, or session-token values
Read messages, account details, or unrelated page content on supported marketplaces
Run content scripts outside the marketplace URL patterns declared in the manifest
Sell extension data for money

When the popup calls Item Value Checker, the browser may attach an existing Item Value Checker signed cookie so the service can recognize a Pro allowance. The extension does not read the cookie value. Data is processed by the service providers described below, and those transfers are part of this policy.

Network requests

The extension makes network requests to:

https://itemvaluechecker.com/api/check-by-url — the current value-check endpoint. Right-click and overlay checks first post the raw image URL. Uploads, pasted images, data URLs, and the fallback for a failed URL-first attempt post base64-encoded image bytes. The service returns a directional result from similar active eBay listings: the filtered asking-price spread and a point estimate 15% below the median ask. Important decisions should be checked against eBay Sold Items.
The source image host — the Item Value Checker backend normally fetches the raw image URL. If that attempt fails, the extension may fetch the image in the browser before resizing and sending the bytes. The image host receives the normal request metadata associated with that fetch.
https://itemvaluechecker.com/api/listing-generator — only when you choose to generate an AI listing draft. The extension sends the checked image bytes and selected marketplace; our backend then sends them to OpenAI to create the requested draft.

Permissions explained

Published and prepared package permissions:

contextMenus — to add the right-click "Check value" menu item
storage — for the local result cache, recent and saved-item history, pending right-click image, overlay setting, and last listing-draft marketplace
Published Chrome Web Store v0.9.4: https://itemvaluechecker.com/* and https://pricelens-api.vercel.app/*. Current runtime requests use Item Value Checker; the legacy PriceLens API host is declared but is not called directly.
Prepared v0.9.5 source: removes the unused legacy host and keeps only https://itemvaluechecker.com/* for value-check and optional listing-draft endpoints. That narrower permission takes effect for Store users only after the new package is uploaded and approved.
Supported marketplace page patterns declared in content_scripts — to read listing image URLs and visible listed prices on Facebook Marketplace, Craigslist, OfferUp, and Mercari and auto-process detected cards while overlays are enabled (the default).

The extension does not request history, tabs, cookies, activeTab, scripting, or <all_urls> permission.

Third parties

Our backend may forward image bytes to eBay's Browse API search_by_image endpoint to find similar active listings. eBay's privacy policy applies to that processing. See eBay's Privacy Policy.

The Item Value Checker backend infrastructure runs on Vercel. See Vercel's Privacy Policy.

If you request an AI listing draft, our backend sends the image and prompt to OpenAI. See OpenAI's Privacy Policy.

Our backend uses Sentry for technical error monitoring, and Chrome may process synced extension settings when browser sync is enabled. The main Item Value Checker privacy policy describes technical information, diagnostics, and server-side retention in more detail.

Children's privacy

The extension is not intended for users under 13. We do not knowingly collect data from children.

Changes to this policy

If this policy changes, we will update the version date at the top of this page and announce changes in the extension's release notes. Continued use of the extension after changes constitutes acceptance.

Contact

Questions or concerns: support@itemvaluechecker.com

Browser Extension Privacy Policy