Best Practices
These recommendations come from running thousands of contextual campaigns. Following them will help you get the most from Classify segments.
Keep targeting lean
Contextual segments work best as the primary targeting layer — not stacked on top of other restrictions.
Adding audience lists, geographic limits, device filters, or inventory allowlists on top of a contextual segment dramatically reduces the available inventory. Each additional filter compounds the restriction, and you quickly end up bidding on a tiny fraction of the addressable supply.
What to avoid:
| Restriction | Why it hurts |
|---|---|
| Audience targeting overlays | Competes with contextual signals — you're paying for context but filtering by cookies |
| Inventory allowlists | Limits delivery to a handful of domains when the segment already curates quality inventory |
| Strict geographic targeting | Contextual content is often global; tight geo targeting cuts most of it |
| Narrow device targeting | Mobile is often the largest share of contextual inventory — excluding it halves your reach |
Classify segments automatically filter out MFA sites and low-quality inventory — see the Optimization Guide for details. You don't need additional brand safety or exclusion lists.
If you need geographic or device constraints, start broad and narrow based on performance data rather than applying them upfront.
Add the Classify pixel to your creatives
The Classify pixel is how you get delivery transparency and post-campaign reporting. Without it, you're flying blind.
Add the pixel as a tracking tag (impression tracker) attached to your creatives in your DSP:
<script src="https://l.csfy.me/je?c={campaign_id}"></script>
Pass DSP macros through the pixel to capture auction-time metadata like the inventory domain, deal ID, and publisher ID. This data powers fraud detection and inventory verification in your campaign reports.
See Pixel Code for the full setup guide and DSP Deal ID Guides for platform-specific instructions on adding tracking tags.
Include cookieless users
Contextual targeting does not rely on cookies, device IDs, or user-level tracking. This is one of its biggest advantages — it works everywhere, including Safari, Firefox, and all cookieless environments.
Make sure your campaign settings do not exclude cookieless users. Many DSPs default to cookie-based environments, which means you may be missing a significant portion of your addressable audience unless you explicitly opt in.
Check your DSP's settings for options like:
- "Include cookieless inventory"
- "Allow Safari/Firefox traffic"
- "Target all environments" (vs. cookie-enabled only)
Set KPIs at activation time
When you activate a segment, you can specify KPI targets that inform how Classify configures the deal:
| KPI | Use when... |
|---|---|
ctr | Optimizing for engagement and click-through |
conversion | Driving specific actions (purchases, sign-ups) |
viewability | Ensuring ads are seen (above the fold, in view) |
vcr | Running video campaigns — optimize for completed views |
cpa | Targeting a specific cost per acquisition |
roas | Maximizing return on ad spend |
Setting a KPI is optional, but it gives Classify a signal for how to weight the segment's optimization.
DSP-specific tips
Each DSP has its own terminology and setup quirks. For detailed platform walkthroughs, see the DSP Deal ID Guides. Here are the highlights:
The Trade Desk — Deal targeting is set at the ad group level. Add the Classify pixel as a "Tracking Tag" under creative settings. TTD supports full macro expansion for inventory domain, deal ID, and publisher metadata.
PubMatic — Add the PubMatic click tracker to your creatives alongside the Classify pixel. PubMatic uses [MACRO] format for macros. See PubMatic macros for the recommended tag format.
Google DV360 — Deals must be added to "My Inventory" at the advertiser level before they can be targeted in line items. DV360 uses ${MACRO} format. Image pixel impression trackers are broadly supported; JavaScript trackers require a third-party tag creative type.
Amazon DSP — Deal targeting is configured in the line item's Supply section. Amazon has a strict creative review process — allow extra time for approval. Macro support is more limited than other platforms.