> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uselayers.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Blocks
> Configurable product recommendation widgets that surface personalized suggestions based on shopper behavior, product similarity, or curated collections.
## Overview
Blocks provide a flexible system for displaying product recommendations across your storefront. Unlike static product lists, blocks dynamically generate recommendations based on context, customer behavior, and configurable rules.
**Key capabilities:**
1. **Multiple anchor types** - Display recommendations on product pages, collection pages, the cart, the home page, search pages, 404 pages, landing pages, and custom surfaces
2. **Flexible strategies** - Choose from interaction-based, similarity-based, or manual curation
3. **Conditional rules** - Modify block behavior based on customer context and product attributes
4. **Safeguards** - Ensure blocks always display appropriately with minimum/maximum constraints and control personalization strength
5. **Fallback chains and trees** - Automatically use alternative blocks — or different chains for different audiences — when primary blocks don't return enough products
6. **Inline performance metrics** - See 7-day impressions, clicks, CTR, add-to-carts, and purchases for each block directly in the dashboard list
7. **Live preview** - Test a block's configuration against real catalog data and shopper context before saving
## Anchor types
Anchor types determine where a block appears on your storefront and what context it uses to generate recommendations.
### Product anchor
Display recommendations on product pages. The block uses the current product as the anchor to find related products.
**Common use cases:**
* "Frequently Bought Together" on product pages
* "Customers Also Viewed" recommendations
* "Similar Products" suggestions
* "Complete the Look" cross-sells
### Collection anchor
Display recommendations on collection pages. The collection is determined dynamically from the `anchor_id` parameter in the API request, which can be either a collection ID or handle.
**How it works:**
* The collection is resolved at request time using the `anchor_id` parameter
* No collection selection is required in the dashboard
* Supports both collection IDs (numeric) and handles (string)
**Common use cases:**
* "Browsed Then Bought" — products purchased by shoppers who browsed the collection
* "Trending in Collection" — products trending within the collection
* Similar products based on the collection's catalog
* Featured products within a collection
* "Editor's Picks" for specific collections
* Collection-specific promotions
### Cart anchor
Display recommendations in the cart. The block uses products currently in the cart to find complementary items.
**Common use cases:**
* "Complete the Look" in cart
* "Frequently Bought Together" based on cart contents
* Cross-sell recommendations before checkout
### Home anchor
Display recommendations on the storefront home page. The block has no anchor product or collection, but trending strategies can use store-wide activity to populate results.
**Common use cases:**
* "Best sellers" and "Trending now" rails
* "Popular in your area" region-aware rails
* Manually curated "Featured products" hero
### Search anchor
Display recommendations on search results pages. The current search query is passed in via the API request context and powers query-aware contextual strategies.
**Common use cases:**
* "Shoppers also viewed" alongside search results
* "Top picks for this search" conversion rails
* Recovery rails on zero-result searches
### Not found anchor
Display recommendations on 404 pages so a missing URL becomes a discovery moment instead of a dead end.
**Common use cases:**
* "You may also like" fallback on 404s
* "Best sellers" or "Trending now" to keep shoppers in the funnel
* Recently viewed re-engagement
### Landing anchor
Display recommendations on campaign landing pages. The traffic source (UTM parameters, marketing channel) is passed in via the request context and can drive contextual strategies.
**Common use cases:**
* Channel-aware "Top picks for this campaign" rails
* Trending rails for launch and promo pages
* Manually curated hero blocks on paid traffic destinations
### Other anchor
Display recommendations on custom storefront pages that don't fit the standard surfaces — about pages, blog posts, custom routes.
**Common use cases:**
* Trending rails on editorial content
* Cross-sell blocks on app or custom pages
* Manually curated placements outside the main funnel
### None anchor
Global blocks that can appear anywhere on your storefront. These blocks require no anchor context and only support the manual strategy.
**Common use cases:**
* Hand-picked "Featured products" on static pages
* Manually curated rails embedded in custom templates
## Block preview
The block editor includes a **Preview** panel that runs the block's current configuration against your live catalog without saving. Use it to:
* Sanity-check anchor selection by entering a real product or collection ID
* Simulate visitor context (geography, marketing channel, device, identity) to verify rule branches
* Compare different strategy and safeguard combinations before publishing
The preview returns the same product results the [Blocks API](/api-reference/blocks) would return for the configured anchor and context, including any active rules and safeguards. Fallback chains and trees are not evaluated in the preview — only the primary block's configuration is run.
## Inline performance metrics
The blocks list shows a 7-day rolling performance summary for each block, refreshed every four hours:
* **Impressions** — number of times the block was rendered (block requests)
* **Clicks** — distinct product views attributed to the block
* **CTR** — clicks ÷ impressions
* **Add to cart** — distinct add-to-cart events attributed to the block
* **Purchases** — distinct purchases attributed to the block
A small sparkline next to each row shows the daily trend across the last seven days. The same metrics are available on merchandising rules — see [Metrics](/platform/metrics) for how attribution works.
Metrics rely on the [attribution token](/api-reference/blocks#response) returned by the Blocks API and forwarded to the [Beacon API](/tracking-api/send-events). Make sure your storefront forwards click, add-to-cart, and purchase events with the block's `attributionToken` for these counts to populate.
## Performance details
Click any row's performance summary on the **Recommendation Blocks** list to open the **Performance** sheet for that block. The sheet provides a deeper view of how a block is converting and which products are driving its results.
The sheet has four sections:
* **KPI cards** — Impressions, CTR, add-to-cart rate, purchase rate, revenue, and revenue per impression (RPI). Each card shows the absolute value and the percent change versus the prior period of the same length.
* **Trend** — A combined line/bar chart showing impressions, clicks, add-to-carts, and purchases across the selected timeframe. Use it to spot day-of-week patterns or campaign spikes.
* **Position** — A breakdown of how the block performs by slot position, helping you understand whether top-positioned products carry the conversion or if engagement spreads evenly across the carousel.
* **Top products** — The products that drove the most impressions, clicks, and revenue for the block. Each row shows the product title alongside its individual performance metrics.
You can switch the timeframe between **7 days**, **14 days**, and **30 days** using the toggle at the top of the sheet. Results are cached briefly per block and timeframe, then refreshed in the background — when fresh data is ready it streams in automatically without requiring a reload.
Click, add-to-cart, and purchase totals on the KPI cards are **blended** — they combine events forwarded with the block's `attributionToken` and modeled events from the same browsing session that happened within ten minutes of the block being shown. The KPI cards expose the deterministic-versus-modeled split so you can see how much of each metric came from each signal. See [Metrics: Blended attribution](/platform/metrics#blended-attribution) for the full breakdown.
The performance sheet uses the same attribution data as the inline metrics. If your storefront isn't forwarding the `attributionToken` to the [Beacon API](/tracking-api/send-events), the sheet will show empty results.
## Bulk actions
The **Recommendation Blocks** list supports multi-select for fast cleanup, audits, and seasonal launches:
1. Click **Select** in the actions column header to enter selection mode.
2. Tick the checkbox on each block you want to act on. Hold **Shift** and click another checkbox to select every row in between.
3. Open the **Actions** dropdown and select one of the bulk actions:
* **Publish** — Activate every selected draft block at once.
* **Unpublish** — Move every selected active block back to draft so it stops returning results, without losing your configuration.
* **Duplicate** — Create a draft copy of each selected block named ` (Copy)`. Duplicates always start as drafts so they never accidentally go live.
* **Delete** — Permanently remove the selected blocks. A confirmation dialog appears before the deletion runs.
Click **Actions** → **Done selecting** to exit selection mode.
<Tip>
Use **Shift+click** on rows when you want to flip a long range of blocks between published and draft for a campaign — for example, unpublishing every clearance block at the end of a sale.
</Tip>
## See also
* [Strategies](/platform/blocks/strategies) - Strategy types and availability by anchor type
* [Rules & Safeguards](/platform/blocks/rules-and-safeguards) - Conditional rules, safeguards, and fallback chains
* [Fallback Chains](/platform/blocks/fallback-chains) - Simple chains and conditional fallback trees
* [Priority & Status](/platform/blocks/priority-and-status) - Block evaluation order and lifecycle
* [Manage blocks in bulk](/help/blocks/bulk-actions) - Publish, duplicate, or delete several blocks at once
* [View block performance](/help/blocks/view-performance) - Open the performance sheet for a block
* [Blocks API Reference](/api-reference/blocks) - API documentation for retrieving block products