Keitaro vs Cometly

If you are down to Keitaro and Cometly, the honest starting point is that these two were built for two different jobs, and for two different kinds of company. Both sit somewhere under the word attribution, but they answer completely different questions. Keitaro is a self-hosted campaign tracker and routing engine for paid-traffic affiliates and media buyers: it stamps every click, splits it to the right lander and offer, and tells you which source made money. Cometly is a B2B SaaS revenue attribution tool: it ties ad spend to money that arrived in Stripe and to deals in a CRM. The reader stuck between them is really deciding what they buy traffic for, not which product is better made.

The honest short version. Keitaro runs on a server you own, prices on a flat license with no click cap, and reads which source, lander and offer made money. Cometly runs in the cloud, meters your monthly pageviews, and ties paid spend to Stripe revenue and a CRM pipeline through the Comet Pixel and server-side events. Which of those two shapes fits how you work is most of the answer.

The one question that decides it: what you buy traffic for

Answer this before you compare a single feature. Do you buy media to offers as an affiliate or media buyer, pushing volume to landers and offers that may live on domains you do not even own? Or do you sell B2B SaaS or a subscription through a longer, sales-assisted funnel that closes in a CRM weeks after the click? If your problem is seeing which source, campaign, lander and offer produced a profit at click-level, across high volume and any traffic type, that is Keitaro's problem to solve. If your problem is knowing which campaign produced a trial that became a paying customer weeks later, and getting that signal back to the ad platforms so they optimize toward revenue instead of raw form fills, that is what Cometly is for.

The business model is not a detail here, it is the decision. Keitaro assumes you run direct-response traffic at scale and want click-level ROI plus your data on your own hardware, which is why it is self-hosted, flat-priced with no click cap, and built to route visitors and read profit by source. Cometly assumes a Stripe subscription or a CRM pipeline and a sale that takes weeks, which is why it writes pre- and post-form touch history onto each deal in HubSpot or Salesforce, the part a CRM's own tracking usually cannot see across a long journey. Put a B2B software closed-won question into Keitaro and it has no pipeline to read. Point high-volume affiliate traffic at Cometly and you are metering a revenue-attribution tool on a job it was never built for. Knowing which of those two sentences describes you settles most of the choice.

Keitaro: own the data, route the traffic, run the box

Keitaro is one of the most established self-hosted trackers media buyers run. Its maker, Apliteni, has shipped it for years and says more than 4,000 businesses run it. It installs on your own Linux server, so your click and conversion data lives on hardware you control, and the price is a flat monthly license with no cap on clicks: a buyer pushing hundreds of millions of pop, push or native clicks a month pays the same tier as one pushing a few million, and the bill never climbs because a campaign won. That flat, uncapped model is the whole reason volume buyers pick it over event-priced cloud trackers.

It is also a real routing engine, not only a tracker. Its filtering splits visitors to different landers and offers across geo, device, OS, browser, connection and source ID, over 35+ tracking parameters, deeper than a cloud tracker built around a single ad account exposes. It fires server-side postbacks to your networks, sends conversions back to Meta, Google and TikTok through their APIs, and pulls ad spend in for real cost and ROI, all on every plan rather than gating cost sync behind a higher tier. A built-in landing page editor, custom domains with SSL and bot filtering keep fewer separate tools between your tracker, your lander and your offer.

Two honest cautions keep it from being an automatic pick. Self-hosting is the real cost and the real risk: the flat license is only as good as the VPS under it, and keeping that machine (CentOS 9 or 10 Stream, 4GB of RAM as the floor) fast, patched and online is your job, not the vendor's. There is no cloud version and no free trial: you buy a license, with a public live demo and a refund policy as the only way to look first. And when server-side tracking breaks, the loudest complaint is slow resolution. The sharpest critical review reports 502 errors on conversion tracking and inaccurate cost attribution, with support acknowledging the problem but giving no timeline, and live chat runs business hours, roughly 06:00 to 16:00 GMT on weekdays. We earn no commission on Keitaro, so there is no affiliate button for it here. The full Keitaro review covers where the depth pays off and where the setup bites.

Cometly: ad spend tied to Stripe and CRM revenue

Cometly does a narrower and, for a software company, more useful thing: it ties ad spend to money that actually arrived. Its Comet Pixel and server-side events feed Stripe revenue and CRM deal stages into the attribution, so you see which campaign produced pipeline and closed-won revenue, with MRR and LTV attached, instead of trusting Meta to grade its own homework. It runs first, last, linear, U-shaped and data-driven models across a long journey, and it sends deal-stage-aware events back to Meta, Google, LinkedIn, TikTok, Microsoft, Reddit and Snapchat through a server-side conversion API on both plans, so bidding optimizes toward paying customers rather than raw leads. Its G2 record is strong and consistent, 4.8 out of 5 across 36 reviews, with praise clustering on tracking accuracy and fast, human support, and one reviewer reported accurate tracking on over $100,000 a month in ad spend.

The two real caveats are commercial, not technical. Cometly publishes no price and offers no free trial: the Core and Enterprise plans are quoted on a sales call, usage-based on your monthly pageviews, and you commit, or at least pay for onboarding, before you see it run on your own traffic. Some buyers report the quote feels high. The honest workaround is to make the live demo prove the tracking on your real numbers first, because that is the only up-front proof you get. Outside its solid but small G2 record the proof thins out, with Trustpilot at 3.6 and no clear Capterra listing. The full Cometly review walks through the setup and the sentiment in detail.

Different jobs, not a better and a worse tool

Underneath the surface, this is not one tool beating another, it is two answers to two different businesses. Keitaro answers which source, lander and offer made money at click-level, at high volume, with the data on hardware you own, and it routes the traffic and pushes those conversions back to Meta, Google and TikTok over CAPI on every plan. Cometly answers which campaign produced recurring revenue for a software company, and feeds that signal back to seven ad platforms. Put a solo B2B founder on Keitaro and they get a fast, deep tracker with no Stripe or CRM connection to tell them which ad produced a paying subscriber. Point a scaling affiliate's pop or push volume at Cometly and they are metering a revenue-attribution tool, on a cloud they do not control, for a job Keitaro does flat-priced on their own server.

So the honest tie-break is not features, it is your operation. If you buy media to offers and live or die by click-level ROI and flat costs, the SaaS-first, cloud-metered attribution tool was never going to serve you. If you sell software or a subscription and need a weeks-long sale tied to the deal in your CRM, the self-hosted tracker has no pipeline to read and no revenue layer to attach. Match the tool to how your revenue actually arrives and the rest of the comparison mostly answers itself. If self-hosting is the specific part of Keitaro you are weighing, our Keitaro vs ClickMagick page runs the self-hosted-against-cloud fork, and Binom vs Keitaro pits it against another self-hosted rival.

Where the pricing diverges

Neither of these prices on the same axis, so you are not modeling a crossover point, you are comparing two shapes. Keitaro is a flat license in euros: €40 a month for Individual Starter, €72 for Advanced and €104 for Expert, then €200 and €400 for its Business tiers, with six- and twelve-month terms taking 10% and 20% off, and CAPI and cost sync on all of them. There is no cap on clicks, but there is a server you rent, patch and keep online, and that cost never shows on the invoice. The economics tip in Keitaro's favour precisely when your click count is large, because nothing about the license moves when your traffic does. Cometly does not publish a price at all: its plans are usage-based on monthly pageviews and quoted on a call, so you cannot line its cost up against a competitor before you talk to sales, and there is no free trial to test it first.

Verify both on your real situation. Keitaro's number is public and flat, but the server it sits on is a real recurring cost and a real operational job, so budget the VPS alongside the license. Push Cometly for a written quote against your actual monthly pageviews, because usage-based pricing climbs quietly as your traffic grows, and confirm what the paid onboarding includes before you commit.

A third path if you host the funnel yourself

Both of these tools measure traffic to pages and checkouts that live somewhere else. Keitaro stamps a click, routes it to a lander and an offer, then catches the conversion as a postback after the fact; Cometly reads revenue out of a Stripe account and a CRM that sit elsewhere too. There is a different way to close the same gap, worth naming because it changes where the data lives. ElasticFunnels is a funnel platform for teams running paid traffic that builds the pages and hosts the checkout itself, and keeps its ad-spend and conversion reporting on the same data layer as those pages, the CRM and the sale. Because a sale closes in a checkout it hosts, that conversion is a first-party event it records directly rather than a postback it has to catch, and it fires server-side postbacks to your affiliate networks on purchase, refund, chargeback and renewal, the network-attribution job Keitaro does for click traffic. It also split-tests page variants under one campaign URL, so a test never resets the ad platform's learning. It starts with a 14-day free trial that takes no card, on plans from $97 a month, plus 0.5% only on revenue processed through its hosted checkout, and nothing on sales you run through outside networks.

The honest limit that keeps it on its own line rather than in the table above: ElasticFunnels is newer than either tool here, and there is very little independent third-party review coverage to check its claims against, so until you run real volume through it you are largely taking the vendor's word for how its reporting and postbacks hold up. That is what you would expect of a platform this recent, where Keitaro has more than 4,000 businesses and a long, if mixed, public record behind it and Cometly a consistent G2 record you can read before you buy. The newness is about the outside proof, not the feature set: the pages, checkout and reporting are usable from day one. And its reporting covers the funnels it hosts, so an affiliate tracking clicks across offers on other people's domains still needs a dedicated router like Keitaro for that traffic, and a B2B SaaS team attributing a sales-led motion that closes in a CRM it runs elsewhere still needs a tool like Cometly. It is an option for the seller who runs their own pages and checkout end to end, not a replacement for either tool.

Which one for you

You buy media to offers as an affiliate or media buyer: Keitaro. Click-level ROI at high volume, deep routing across 35+ parameters, a flat license that never meters your clicks, and your data on your own server are the right call for pop, push, native and direct-response traffic, with CAPI and cost sync on every plan. Budget the VPS and the setup time, and lean on the live demo and one small campaign to prove it before you commit.

You sell B2B SaaS or a subscription and need ad spend tied to revenue: Cometly. Stripe and CRM revenue attribution, long-journey multi-touch models and server-side conversion feeds to seven ad platforms are the right fit, as long as you can commit without a public price or a free trial and you make the demo prove the tracking on your own numbers first.

You host your own pages and checkout end to end: look at ElasticFunnels alongside them, with the newness caveat above in mind, and keep a router like Keitaro for any traffic that closes on domains you do not host, or Cometly for a software sale that closes in your CRM.

Keitaro takes our default pick here, not because it out-measures Cometly at Cometly's own job, but because more readers who reach this comparison buy media to offers than sell B2B software. On its own turf, a B2B SaaS or subscription company tying ad spend to Stripe revenue and a CRM pipeline, Cometly is plainly the better tool, and we would pick it every time over a click tracker with no pipeline to read. If you are actually weighing attribution tools for a software business, our Northbeam vs Cometly and Binom vs Cometly comparisons take the next step. If you are choosing between trackers instead, Keitaro vs AnyTrack and CPV Lab Pro vs Cometly are the ones to read, and you can see where Keitaro lands overall in our ad tracker ranking and the full list of head-to-heads.