Meelu

Free attribution model tool

Your reports hand the whole sale to whatever someone clicked last, so the channels that started the journey look like they do nothing. Upload a GA4 conversion paths export and see the same conversions split eight different ways — including two worked out from your own customer journeys rather than from a rule. The headline number is the one nobody shows you: how many conversions and how much revenue your reports are crediting to the wrong channel.

Drop your GA4 conversion paths export here, or

A path column like Organic Search > Direct with a conversions count — or a raw touchpoint log with a user id, a channel and a converted flag. Up to 100,000 rows.

The GA4 sample has no failed journeys in it, which is normal and which limits what the models can say. The touchpoint log has them, so it gets the full rate-based Shapley model — the difference is worth seeing.

Every model runs in this browser tab. The file never reaches our server, so there is nothing for us to keep.

  • No account
  • Nothing uploaded
  • Eight models side by side
  • Conversions and revenue
  • CSV export

What this attribution modeling tool does

Shows what last click is getting wrong

For every channel, the gap between the credit your reports give it and the credit its real role in the journey earns it — in conversions and in pounds. That gap is the reason the tool exists.

Finds the channels doing quiet work

A channel that turns up in the middle of most of your winning journeys scores nothing under last click. Here it shows up, because the credit follows how much the journeys depend on it.

Spots channels that bring the wrong people

A channel can pull in a lot of visits that rarely buy. Instead of rewarding it for showing up a lot, the report can mark it down — and you see it before you put more money behind it.

Eight ways of splitting the credit, side by side

The common rules — all to the last click, all to the first, split evenly, weighted towards recent touches, weighted to the ends — next to two splits worked out from your own data. One table.

Change an assumption, see what it costs

How quickly older touches lose credit, whether repeat visits to the same channel count once or twice. Change one and the whole report redraws, so you can see which conclusions are solid.

CSV export, nothing uploaded

Every split, every channel, conversions and revenue side by side, ready to paste into a budget argument. The whole thing runs in your browser tab.

How to build a multi touch attribution model from a GA4 export

  1. Step 1

    Export your conversion paths

    In GA4: Advertising → Attribution → Conversion paths. Choose how far back to look and the conversion you care about, then export to CSV. Your own export works too, as long as each row has something to identify the customer, the channel that touched them, and whether they bought.

  2. Step 2

    Drop the file in

    The columns are picked for you and shown on screen so you can correct them if it guessed wrong. Nothing leaves the browser tab.

  3. Step 3

    Read the gap, then go and test it

    See which channels your reports are short-changing, in conversions and revenue. Then run a real test — turn one of them off in a region, or hold it back for a few weeks — because only that proves the channel is causing the sales.

The eight models, and what each one assumes

An attribution model comparison is only useful if you know what each column is claiming. These are the eight in the table.

Last click
All credit to the final touch. The default in most reports and the reason Direct, brand search and retargeting look like heroes. It answers “what was the last thing that happened”, which is not the same question as “what worked”.
Last non-direct click
Last click, skipping back past Direct. Universal Analytics' old default. Worth running purely to see how much of your last-click credit was sitting in the untracked bin.
First click
All credit to whatever started the journey. Over-credits discovery channels the same way last click over-credits closing ones. Useful as the other end of the bracket in a first click vs last click attribution comparison, not as a reporting standard.
Linear
Credit split evenly across every touch. Honest about knowing nothing, which is more than can be said for the single-touch rules, but it treats a display impression and the email that closed the sale as equals.
Time decay
The closer a touch was to the sale, the more credit it gets. Fine for a purchase someone decides on in a week, badly wrong for one that takes nine months — that setting would wipe out everything that introduced the customer in the first place. Set it to something your sales cycle recognises.
Position-based
Most of the credit to the first and last touches, the rest shared by everything in between. A compromise between the two single-touch rules, with the split picked by convention rather than by anything in your data.
Markov chain
Worked out from your data. It asks what would happen to your conversions if a channel vanished from your customers' journeys, and gives credit in proportion to how much you would lose. It rewards being load-bearing rather than being last.
Shapley value
Worked out from your data. It asks what each channel adds on average when you bring the channels together in every possible order. A channel that pulls in a lot of visitors who rarely buy can score below zero here, and the tool says so rather than rounding it up to something polite.

What it does not do

  • It cannot prove a channel caused the sale. Every split here describes the journeys that happened. None of them can tell you what would have happened if you had switched a channel off, and a channel that shows up in most winning journeys may just be riding along on demand it never created. Only a real test settles that — switch the channel off in one region and compare. Use this to pick the one or two channels worth testing, then go and test them.
  • It only sees the paths GA4 stitched together. Cross-device journeys, cookie-blocked browsers, consent refusals, iOS privacy limits and lookback windows shorter than your sales cycle all drop touches — and the touches they drop are disproportionately the early ones, which is exactly the part these models exist to value.
  • Direct is a bin, not a channel. It absorbs dark social, app traffic, pasted links, referrer-stripping email clients and every mistagged campaign you have ever run. Some of whatever credit it collects belongs to something you cannot see, whichever model you run.
  • It needs a decent number of conversions. A handful of sales gives you a noisy answer that will change next month. It also works better if your file includes the people who never bought — a GA4 conversion paths export only contains the journeys that ended in a sale, which limits how much the tool can tell you about which channels actually convert.
  • It says nothing about spend. Attribution divides conversions among the channels in a path. It does not know what anything cost, has no view on diminishing returns, and cannot answer “what if I moved £10k from display to paid search”. That is a marketing mix model question.
  • It will not match GA4 exactly. GA4’s data-driven attribution runs on event-level data you cannot download, with a model you cannot inspect. This runs on the export you can. Treat a difference as information about the assumptions, not as one of them being broken.
  • No view-through, no impressions. A conversion paths export contains clicks and sessions. Display and video impressions that never produced a session are invisible here, so channels that work mainly by being seen will be under-credited by every model on the page.

Frequently asked questions

What is an attribution model?

An attribution model is a rule for splitting the credit for a conversion across the marketing touchpoints that came before it. Someone might find you through organic search, return from an email, click a paid ad and then buy. That is one sale and three channels, and the model decides who gets what share. Different models give different answers to the same data, because there is no single correct split, only the rule you chose.

What is the difference between first-click and last-click attribution?

Last-click attribution gives all the credit to the final touchpoint before the conversion, and first-click gives it all to the first one. Last click favours channels people use when they already intend to buy, such as brand search and retargeting. First click favours discovery channels such as organic search, social and display. Both are wrong in the same way: they hand 100% of the credit to one interaction in a journey that had several.

What is multi-touch attribution?

Multi-touch attribution spreads credit for a conversion across every touchpoint in the journey rather than giving it all to one. Linear splits it evenly, time decay weights touchpoints nearer the conversion more heavily, and position-based typically gives 40% each to the first and last touch with the rest shared between the middle. It gives a fairer picture of how channels work together, but the weightings are still assumptions you picked rather than anything measured.

What is data-driven attribution?

Data-driven attribution works out the credit split from your own conversion data instead of applying a fixed rule. Algorithms such as Markov chains measure how much your conversion rate drops when a channel is removed from the journey, while Shapley values calculate each channel's average contribution across every possible ordering. The result reflects how your customers actually behave rather than a rule someone chose. It needs a decent volume of conversions to be stable, so low-traffic accounts get noisy answers.

Which attribution model is the most accurate?

No model is accurate in the strict sense, because attribution is a credit allocation, not a measurement. Data-driven models such as Markov and Shapley come closest to reflecting real behaviour, since they are derived from your journeys rather than assumed. That said, they can only see touchpoints you track, so offline exposure, word of mouth and view-through effects are invisible to all of them. The usual practice is to compare several models and act on where they disagree.

What is last non-direct click attribution?

Last non-direct click gives the credit to the last touchpoint before the conversion that was not direct traffic. It exists because direct usually means someone typing your URL after another channel introduced them, so crediting direct tells you nothing actionable. It is the default in many analytics tools for that reason. It is still last-click logic with one exception bolted on.

Why does attribution matter for marketing budgets?

Because the model decides which channels look like they are working, and budgets follow that. Last click systematically underfunds awareness channels, which rarely appear at the end of a journey, and overfunds brand search and retargeting, which almost always do. Switch models and the same spend can look like a success or a waste. Comparing models before reallocating budget is the point of doing attribution at all.

How long should an attribution lookback window be?

Thirty days is the common default, and it suits most ecommerce. Considered purchases with long research phases, such as B2B software or cars, often need 60 or 90 days to capture the first touch at all. A window that is too short makes discovery channels disappear, while one that is too long credits touchpoints that had nothing to do with the sale. Set it from your actual time-to-purchase rather than the default.

Attribution is one of three answers

Attribution tells you about paths. A marketing mix model tells you about spend — it compares what you put into each channel over time with what came back, so it can see where extra money stops paying off and it does not care whether anyone was tracked. The two disagree constantly, and where they disagree is the most interesting thing either of them produces. Run both on the same period before you argue with anyone about budget.

And when a channel’s numbers move suddenly, neither model is the right first stop. The traffic drop analyser exists to work out whether anything really changed, before you move budget on the strength of a wobble in a report.

All three are pieces of Meelu, a desktop app where an AI marketing agent runs your marketing on your own machine — your exports, your models, nothing leaving the laptop. Join the waitlist.