Is OpenSEO really free?

Yes. OpenSEO is open source: the code is public and installing it costs nothing. At most you pay for hosting if you put it on a server, often a few euros a month. Semrush, on the other hand, costs €134 a month. One nuance for OpenSEO: the software is free, but the SEO data comes from DataForSEO and is paid as you go, a few cents per request, with a starting top up of 50 dollars (around €45). No subscription, but not zero either.

Do I need to code to install OpenSEO?

No. The level is intermediate and the install takes about 20 minutes with the prompt from the page: Claude does the work, you answer its questions.

How is it different from Semrush?

OpenSEO does most of what Semrush does, without a subscription, and your data stays with you. The point by point comparison is on the page.

Yes. With an open source tool installed on your side, your files stay on your machine or your server. Nobody can close your account or change the price.

Free alternative

Free alternative to Semrush

Semrush costs €134 a month. OpenSEO does the same job for free, in open source: you install it on your machine or a small server, and you stop paying.

Public entry price, taken from Semrush’s website (semrush.com). Over a year, that is €1608 that stays in your pocket.

What replaces Semrush

The main alternative

OpenSEO

🟡 Intermediate⏱️ ~20 min to installSave €134/mo

OpenSEO calls itself "the open source alternative to Semrush and Ahrefs", and the repository took off within months: over 19,000 stars, MIT licence, a release every couple of weeks. On the menu: keyword research (volume, difficulty, intent, the results page), competitor domain overview, backlinks and referring domains, rank tracking over time, technical site audit, and two recent tools the big players do not have yet: your brand's visibility in ChatGPT style answers, and an AI prompt explorer. It also speaks MCP: you can ask your SEO questions straight from Claude or Cursor. The thing to understand before installing: the software is free, but the SEO data comes from DataForSEO, a provider you pay as you go with your own key (about 5 cents for a keyword research, 8 cents for a domain overview, minimum top up of 50 dollars, around €45). For a small site that is a few euros a month, not 134. If you would rather host nothing, the vendor offers a hosted version at 10 dollars a month (around €9), credits included.

Loucash’s verdict on OpenSEO

7/10

If you pay Semrush or Ahrefs for one or two sites, OpenSEO covers the essentials: keywords, backlinks, rankings, audit, plus AI visibility and an MCP server to do your SEO from Claude. The software is truly free and open source, and it even runs on Cloudflare's free plan. What I like: the project's pace (19,000 stars in under seven months, a release every couple of weeks), pay per request rather than a subscription, and the AI angle nobody else offers in open source. What may bite: it is not free end to end. The data comes from DataForSEO, you need an account and a minimum top up of 50 dollars (around €45), then every request is deducted (a few cents). For a small site that is a few euros a month, but if you fire a thousand requests a day, do the maths. The project is young (version 0.1), the Docker version runs without a password and must never be exposed as is, and the AI features need an extra OpenRouter key.

Who it is for: You do SEO for one or two sites, you pay Semrush or Ahrefs for a few searches a week, and you want your data at home. If you run thousands of requests a day, compare the pay as you go cost first.

See the full page →See the tool ↗

OpenSEO versus Semrush: the match

Price
OpenSEO
€0 for the tool, data pay as you go (a few cents per request)
Semrush
€134/month, €112.52 yearly
Tracked keywords
OpenSEO
As many as you want, you pay per request
Semrush
500 on the SEO plan
Keyword research
OpenSEO
Volume, difficulty, intent, SERP
Semrush
Yes, proprietary database

Semrush ↗

VS	OpenSEO	Semrush ↗
Price	€0 for the tool, data pay as you go (a few cents per request)	€134/month, €112.52 yearly
Tracked keywords	As many as you want, you pay per request	500 on the SEO plan
Keyword research	Volume, difficulty, intent, SERP	Yes, proprietary database
Backlinks	Yes, via DataForSEO	Yes, proprietary database
AI visibility	ChatGPT mentions and citations, prompt explorer	As an add on, on higher plans
From Claude or Cursor	Yes, built in MCP server	No
Where your data lives	At home (Docker) or on your Cloudflare account	At Semrush

The prompt that installs OpenSEO

Paste this prompt into Claude: it checks the repository, asks you its questions and installs the tool step by step.

Je veux installer OpenSEO (outil SEO open source, dépôt GitHub every-app/open-seo, site openseo.so) à la place de Semrush ou Ahrefs. Demande-moi d'abord si je veux l'essayer sur ma machine avec Docker (docs/SELF_HOSTING_DOCKER.md du dépôt) ou l'héberger sur Cloudflare avec le plan gratuit (docs/SELF_HOSTING_CLOUDFLARE.md), puis suis la doc officielle pas à pas. Guide-moi pour créer un compte DataForSEO et une clé d'API (docs/DATAFORSEO_API_KEY.md), en me prévenant que les données se paient à l'usage avec un dépôt minimum de 50 dollars, et mets la clé dans le fichier .env. En mode Docker, rappelle-moi que l'application tourne sans authentification et ne doit pas être exposée sur internet sans protection. Si je veux les fonctions IA, propose-moi d'ajouter une clé OpenRouter. Lance l'outil, ouvre-le dans mon navigateur, et fais-moi faire une première recherche de mots-clés sur mon domaine pour vérifier que les données arrivent. Explique-moi comment suivre ma consommation chez DataForSEO et comment mettre OpenSEO à jour.

Review the GitHub repository and check whether it is safe to install given my machine and my infrastructure. Ask me as many questions as possible, using widgets, to clarify my request and be as precise as you can.

Frequently asked questions

Is OpenSEO really free?: Yes. OpenSEO is open source: the code is public and installing it costs nothing. At most you pay for hosting if you put it on a server, often a few euros a month. Semrush, on the other hand, costs €134 a month. One nuance for OpenSEO: the software is free, but the SEO data comes from DataForSEO and is paid as you go, a few cents per request, with a starting top up of 50 dollars (around €45). No subscription, but not zero either.
Do I need to code to install OpenSEO?: No. The level is intermediate and the install takes about 20 minutes with the prompt from the page: Claude does the work, you answer its questions.
How is it different from Semrush?: OpenSEO does most of what Semrush does, without a subscription, and your data stays with you. The point by point comparison is on the page.
Do I own my data?: Yes. With an open source tool installed on your side, your files stay on your machine or your server. Nobody can close your account or change the price.

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