Understanding data differences

A figure in Vendlen that does not match Amazon’s own console is usually not an error. It is almost always one of five things, and knowing which saves a lot of time.

1. The window is not the same

The most common cause by far.

Amazon’s console and Vendlen can both be showing “last 30 days” and mean different date ranges, because the boundary depends on the marketplace day, the timezone, and whether today counts.

Check the exact dates, not the label. Two reports labelled the same rarely cover the same days.

2. Attribution is still arriving

Amazon attributes a sale to the click that led to it, and that click may have been days earlier. So recent figures go up after the fact — sometimes for a couple of weeks.

The practical consequences:

• The last few days always understate orders and sales.
• A report you took yesterday will not match the same report today.
• This is why Automation ignores the most recent days by default. See Data Window.

If you are comparing a recent period, compare it against a report taken at the same time, not against one you saved a week ago.

3. The metrics cover different ad types

This one surprises people, because both numbers are called ACOS.

Metric	Covers
Ad sales, ad spend, ACOS, TACOS	Sponsored Products, Display, Brands and Brands Video
Impressions, clicks, orders, CPC, CTR, conversion	Sponsored Products and Display only

Sponsored Brands advertises several products at once, and Amazon does not report its spend per ASIN. Vendlen allocates those values to ASINs by daily product sales.

That allocation is an estimate. A per-ASIN ACOS that includes allocated Brands spend will not match a per-campaign ACOS that does not. Neither is wrong — they answer different questions.

4. The data has not synced yet

Vendlen reads on a schedule, not on demand. A change you made in Amazon a few minutes ago will not be here until the next sync.

Check the latest-data date on the Connections tab. See Amazon connections.

5. ACOS and TACOS are not the same measure

ACOS is ad spend against ad sales. TACOS is ad spend against total sales, organic included. Comparing one against the other will always show a gap, and the gap is the point rather than an error.

When a difference is a problem

Most differences resolve into the five above. Treat it as a real problem when:

• The latest-data date has stopped moving, which means syncing is failing quietly rather than lagging.
• The SP-API sync reports a non-zero error count, which means part of the catalog did not arrive.
• The gap is large and stable — attribution lag shrinks as data settles, so a difference that does not close over a week is not lag.
• Whole entities are missing, rather than figures being slightly off.

Still not adding up?

If you have checked the dates, allowed for attribution, and the gap does not close, get in touch with a concrete example — the entity, the date range, the number Vendlen shows and the number Amazon shows. That is far faster to diagnose than a general report.

Contact Vendlen