One View for Meta, Google and LinkedIn Ads: Cross-Channel Ad Reporting
Why Platform Numbers Never Add Up, and How to Build a Report That Does
Short answer
Cross-channel ad reporting works when conversions come from one source of truth, not from adding up platform claims. Combine only what platforms measure the same way, like spend, impressions and clicks, and take conversions from your shop, CRM or analytics. Keep each platform's own count as a secondary column.
1. Why don't conversion numbers from different ad platforms add up?
Because each platform credits conversions using its own attribution window, may count people who only viewed an ad, and has no visibility of the other platforms. One purchase can be claimed by all three.
- Attribution window
- The number of days after someone clicks or views an ad during which an ad platform will credit a conversion to that ad.
- Also known as: Conversion window, Lookback window
- Full definition of Attribution window
A customer sees a LinkedIn ad on Monday, clicks a Meta ad on Wednesday and searches your brand on Google on Friday, clicks the ad and buys. LinkedIn may count a view-through conversion, Meta a click-through conversion within its window, and Google a click conversion. The business made one sale; the three dashboards report three.
| Platform | Default click window | Default view window | Where it is set |
|---|---|---|---|
| Meta Ads | 7 days | 1 day | Attribution setting on each ad set [s1] |
| Google Ads | 30 days for most conversion actions | 1 day for view-through | Per conversion action [s2] |
| LinkedIn Ads | 30 days | 7 days | Per conversion [s3] |
None of the platforms is lying. Each is answering "did our ad play a part?", which is a different question from "which channel caused the sale?". Cross-channel reporting is about not confusing the two.
2. Which numbers can I combine across platforms, and which can I not?
Spend can be summed. Impressions and clicks can be summed with care over definitions. Reach cannot be summed, because the same people appear on several platforms. Platform-reported conversions should never be summed.
| Metric | Combine? | Why | What to do |
|---|---|---|---|
| Spend | Yes | Money is money, once currency and dates match | Sum after converting to one currency |
| Impressions | With care | Counted similarly, but viewability rules differ | Sum, and do not compare CPMs across platforms as if equal |
| Clicks | With care | Some platforms count all clicks, others link clicks | Use link or destination clicks where available |
| Reach | No | The same person is reached on several platforms | Report per platform only |
| Platform-reported conversions | No | Each platform claims every conversion it touched | Report per platform, as a secondary column |
| Conversions from your source of truth | Yes | Counted once, by you | Use for totals and blended cost per conversion |
3. How do metric names map between Meta and Google Ads?
Most concepts exist on both platforms under different labels. A small dictionary, agreed once and kept with the report, stops the team comparing different things under the same heading.
| Report column | Meta Ads Manager | Google Ads | Note |
|---|---|---|---|
| Spend | Amount spent | Cost | Convert to one currency |
| Impressions | Impressions | Impr. | Comparable with care |
| Clicks to site | Link clicks | Clicks | Meta also shows Clicks (all), which is wider |
| Click-through rate | CTR (link click-through rate) | CTR | Use the link version on Meta |
| Platform conversions | Results, for a conversion objective | Conversions | Different windows and models |
| Cost per platform conversion | Cost per result | Cost / conv. | Only comparable within a platform |
4. What should be the source of truth for conversions?
The system that records the sale or lead once: your shop, your CRM, or your analytics with UTM-tagged links. Use it for totals and for blended cost per conversion, and use platform numbers to compare campaigns within each platform.
The source of truth does not have to be perfect. It has to count each conversion once, apply the same rule to every channel, and stay the same from month to month. A shop or CRM does that for sales and leads. Analytics with consistent UTM parameters does that for sessions and conversions by source, with the known weakness that it under-credits channels people see but do not click.
The two numbers every cross-channel report needs:
- Blended cost per conversion: total ad spend across all platforms divided by total conversions from your source of truth. This is the number that tells you whether paid media as a whole is working.
- Channel share from your source of truth: conversions by UTM source, next to each platform's own claim. The gap between the two is information, not error: a platform that claims far more than analytics credits it with is either driving views that lead to later searches, or over-claiming.
The guides on attribution for small teams and on UTM parameters for social media cover choosing one model and tagging links consistently, which is most of the work.
5. How do I build a weekly cross-channel ad report?
Export the same date range from each platform, align currency and time zone, map the columns to your dictionary, add conversions from your source of truth, and write one line of interpretation per channel.
- Fix the date range and time zone. Use the last seven full days, Monday to Sunday. Check each ad account's time zone setting, because accounts in different time zones cut days at different hours and daily figures will not line up.
- Export the same columns from each platform. Spend, impressions, destination clicks, CTR and platform conversions, using the dictionary. Save the column set in each platform so the export takes a minute.
- Convert to one currency. If accounts bill in different currencies, convert at one fixed rate for the week and note it. Mixing currencies silently is a common reason blended numbers look wrong.
- Add your source-of-truth conversions. Pull conversions by UTM source from analytics, or by channel from your shop or CRM, for the same week. Put them next to each platform's own claim.
- Calculate the blended number. Total spend divided by total source-of-truth conversions. Track it weekly; it is the one line that answers whether paid media is paying.
- Write one sentence per channel. What changed, why you think so, and what you will do. A report without interpretation gets skimmed; one sentence is enough to make it read.
| Channel | Spend | Impressions | Destination clicks | CTR | Platform-reported conversions | Source-of-truth conversions | Note |
|---|---|---|---|---|---|---|---|
| Meta | One sentence | ||||||
| Google Ads | One sentence | ||||||
| One sentence | |||||||
| Total | Sum | Sum | Sum | Do not average | Do not sum | Sum | Blended cost per conversion |
6. Which cross-channel reporting mistakes cost the most?
Summing platform conversions, comparing CTR or CPM across platforms as if they were equal, mixing objectives, and changing windows or models mid-quarter. Each produces a confident number that is wrong.
- Summing platform conversions and reporting the total as sales. It overstates results, sometimes badly, and the error grows with every platform you add.
- Comparing CPMs across platforms. Audiences, formats and auctions differ; a cheaper CPM is not a better channel.
- Mixing campaigns with different objectives in one row. An awareness campaign and a sales campaign on the same platform should not share a cost per conversion.
- Changing attribution windows or models mid-quarter. Every comparison with earlier weeks breaks, and nobody remembers why the numbers jumped.
- Judging a channel on one week. Small volumes are noisy; look at four-week trends before moving budget.
On Basic and above, Oppira connects your own Meta, Google, LinkedIn, TikTok, Pinterest and X ad accounts read-only, so spend, performance and creatives sit in one view rather than six exports. On Pro, the CLI can pull the same data in a script, for example with oppira ads performance --from 2026-06-01, and you can manage your ads from Oppira with every change approved first.
Key Takeaways
Every platform claims every conversion it touched
One sale can appear in Meta, Google and LinkedIn at once. Never add platform-reported conversions together.
Windows differ by default
Meta defaults to 7-day click and 1-day view, Google Ads to 30-day click, LinkedIn to 30-day click and 7-day view.
Sum spend, not reach
Spend, impressions and clicks can be combined with care. Reach and platform conversions cannot.
One source of truth for conversions
Your shop, CRM or UTM-tagged analytics counts each conversion once. Use it for totals.
Blended cost per conversion is the headline
Total spend divided by source-of-truth conversions tells you whether paid media as a whole is working.
Write a metric dictionary
Map each report column to each platform's label and definition, and use destination-click CTR everywhere.
Frequently Asked Questions
Sources
- About attribution models and attribution settings Meta Business Help Center, September 2026.
- About conversion windows Google Ads Help, September 2026.Default click-through and view-through conversion windows for new conversion actions.
- LinkedIn conversion window LinkedIn Marketing Solutions Help, September 2026.
- CTR (all) Meta Business Help Center, September 2026.
Explore More
Related analyses, benchmarks, and industry insights
Related Guides
Glossary Terms
Turn reading into a reaction
Oppira watches your competitors, keeps your playbook current, and drafts the response. See your market clearly by tomorrow.