How to optimize product feed for CSEs?

Use clean titles with brand + attributes, high-res images, correct GTIN/MPN, competitive pricing, accurate stock and tailored categories per channel.

How much does ComparisonEngines cost?

Plans start free for up to 500 SKUs. Pro and Scale plans add automation, bidding and multi-country feeds.

ComparisonEngines — Compare, Optimize & Win Every Shopping Engine in 2026

Q: What is a comparison shopping engine?

A comparison shopping engine (CSE) aggregates product listings from many merchants so shoppers can compare price, shipping, reviews and availability in one place. Examples: Google Shopping, Idealo, Kelkoo, PriceGrabber.

Google Shopping ✦ Idealo ✦ Kelkoo ✦ PriceGrabber ✦ Shopping.com ✦ Shopzilla ✦ Amazon ✦ eBay ✦ Billiger.de ✦ Geizhals ✦ Ceneo ✦ Twenga ✦Google Shopping ✦ Idealo ✦ Kelkoo ✦ PriceGrabber ✦ Shopping.com ✦ Shopzilla ✦ Amazon ✦ eBay ✦ Billiger.de ✦ Geizhals ✦ Ceneo ✦ Twenga ✦

Team optimizing comparison engines feeds

✓

Since 2011 — 12k stores scaled
We started as price-comparison affiliates. Now we run feeds for brands in 28 countries.

01 — About ComparisonEngines

We turn messy catalogs into money machines on every comparison site.

Shoppers don't start on your site. They start on comparison engines — comparing 14 offers in 8 seconds. If your title is truncated, image is grey, price without shipping, you lose. We fix all of it automatically, every 15 minutes, for every channel.

✓Feed Doctor AI: fixes 127 error types — GTIN, MPN, taxonomy, sizes, colors, shipping, availability. 98.6% approval rate on Google Merchant Center.
✓Price & Bid Brain: reprices vs competitors and shifts budget to engines + keywords with highest margin, not just clicks.
✓One dashboard: Shopify, WooCommerce, Magento, BigCommerce, custom XML/CSV/API — synced to 42 CSEs + marketplaces.
✓Built for 2026: AI titles, background removal, video from images, Performance Max + free listings + social commerce.

Explore platform See 42 engines

02 — Coverage

All engines. One login.

Global giants + local price heroes. We localize currency, language, tax, shipping and categories per country.

Global • CPC + Free

Google Shopping

Merchant Center, PMax, free listings, CSS optimization. Feed every 15 min.

ROAS 4.8x

EU • DE/FR/UK

Idealo + Kelkoo

Offer API, best-price logic, shipping cost handling, review stars sync.

ROAS 3.9x

US Classic

PriceGrabber + Shopping.com

Taxonomy mapping, daily FTP, bid rules by category & margin.

CPC from $0.12

Marketplaces

Amazon + eBay

ASIN matching, repricer guardrails, stock buffer to avoid oversell.

+31% BuyBox

Engine	Region	Model	Best for	Avg CPC
Google Shopping	Global	CPC / Free	Scale + intent	$0.42
Idealo	DE, AT, ES, IT, FR, UK	CPC	Electronics, home	€0.38
Kelkoo	19 countries	CPC	Fashion, sports	€0.31
PriceGrabber	US	CPC	Tech, appliances	$0.28
Shopping.com / Shopzilla	US, UK	CPC	Long-tail SKUs	$0.19
Geizhals / Billiger.de / Ceneo	DACH + PL	CPC / CPA	Price fighters	€0.24

03 — Platform

Feed magic + bid science

Everything you need to dominate comparison results — without 6 tools and CSV hell.

AI Feed Doctor

Self-healing product data

Auto-fix titles, images, GTINs, sizes, colors. A/B test titles per engine. Bulk rewrite 50k SKUs in minutes with brand voice preserved.

Bid Brain 2.0

Margin-based bidding

Stop bidding equal for €9 margin and €190 margin. Rules + ML shift spend hourly to winners, pause losers, protect price wars.

Price Radar

Spy competitors 24/7

Track 2M+ offers daily. Get alerts when you're undercut, auto-adjust or highlight free shipping / warranty to win without racing to bottom.

⚡ 15-min sync

Price & stock freshness prevents disapprovals and oversell. Shopify, Woo, Magento, Mirakl, Channable import supported.

🎨 Creative booster

Background removal, infographics, size overlays, video slideshow from 3 images. +27% CTR on visual engines.

📊 Profit analytics

True profit after COGS, shipping, returns, fees per SKU per engine. Kill vanity revenue.

04 — How it works

Live in 4 steps, 1 day.

Start now

Connect catalog

Plugin or feed URL. We pull products, images, stock, prices. No dev needed — 11 minutes average.

Clean & enrich

AI fixes errors, maps 5,800 categories, translates to 14 languages, adds missing attributes.

Push everywhere

One click to 42 engines. Tailored titles, prices with shipping, per-country rules. Approval in hours.

Scale profitably

Autobidding + price radar + weekly growth sprints with our CSE specialists.

05 — Proof

Loved by performance teams

"We went from 61% disapproved to 99.2% approved in 9 days. Idealo ROAS jumped from 2.1 to 5.3 without raising spend."

Lena Hoffmann
Head of Ecom, ElectroHub.de

"Bid Brain killed 3,200 loser keywords automatically. CPC -41%, profit +68%. Best tool we pay for, period."

Marcus Bell
Founder, GearUp US

"One feed to Google, Kelkoo, Ceneo + Amazon. Translation + tax logic saved us a full hire. Expansion to 6 countries in a month."

Sofia Marini
CMO, CasaViva

06 — Pricing

Pay for profit, not clicks

Free audit + 14-day Pro trial. Cancel anytime. No % of ad spend on Starter.

Starter

€0

Up to 500 SKUs • 2 engines • daily sync • feed health check

✓ Google free listings
✓ 1 country
✓ Email support

Start free

€99/mo

Up to 10k SKUs • 12 engines • 15-min sync • Bid Brain • Price Radar

✓ AI titles + image booster
✓ 5 countries + translation
✓ Profit analytics + Slack alerts

Try 14 days free

Scale / Agency

Custom

Unlimited SKUs • 42 engines • API • dedicated CSE strategist • SLA

✓ Custom repricer + ERP
✓ White-label reports
✓ Quarterly growth sprints

Book demo

07 — FAQ

Questions? Answers.

Everything merchants ask before switching to ComparisonEngines. Still curious? Talk to us.

Support team helping with comparison engines

What is a comparison shopping engine? +

A CSE collects product offers from hundreds of shops so buyers compare price, shipping, availability and reviews side-by-side. Google Shopping, Idealo, Kelkoo, PriceGrabber, Billiger.de are classic examples. 68% of EU electronics purchases start there.

Which engines should I start with? +

Google Shopping everywhere + 1-2 local leaders: Idealo/Kelkoo in EU, PriceGrabber/Shopping.com in US, Ceneo in PL. We analyze your category margin and recommend top 3 by profit potential, not volume.

Do you replace my agency? +

No — we supercharge them. Agencies use our automation + analytics to manage 10x more SKUs. Or use our managed service if you have no PPC team.

How fast will I see results? +

Feed approval lift in 3-7 days, CTR lift in 2 weeks, ROAS lift typically 30-80% in 45 days. Price Radar often finds 5-10% wasted spend on day one.

Can I keep my shop system? +

Yes. Native plugins for Shopify, WooCommerce, Shopware, Magento, PrestaShop, BigCommerce + any CSV/XML/API. No migration.

08 — Newsroom

Latest from the comparison world

Feed tactics, engine updates, case studies. Click to read full story.

Oct 27, 2026 • CSE Insights

Iptv 4k Portugal

Meta Title: IPTV Comparison Guide: Best Sports Streaming in Portugal Meta Description: Compare IPTV services in Portugal. Discov…

Read full →

GET YOUR FREE CSE AUDIT — WORTH €499

We check your feed on 5 engines, spy 10 competitors, and show 3 quick wins in 48h. No strings.

Claim audit See process

09 — Contact

Let's compare your growth.

Berlin • London • New York • Warsaw. Reply in < 4 business hours.

📧 hello@comparisonengines.com
For demos, onboarding, support

📞 +49 30 555 013 42
Mon–Fri 9–18 CET • EN/DE/PL

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