Lettertrace
A free, open-source tool that tracks how often and how favorably Claude, ChatGPT, and Gemini mention your brand — like Google Analytics, but for AI answers instead of web traffic.
🔗 Visit Lettertrace
Description
Search is changing: more people ask ChatGPT or Claude for a recommendation than type a query into Google. That shift creates a blind spot for any business — you have no idea if AI assistants mention you at all, or if they send potential customers straight to a competitor instead. Lettertrace closes that gap by regularly asking AI models natural-sounding questions about your industry and logging whether, and how, your brand comes up.
It runs automated daily or weekly checks across Claude, ChatGPT, Gemini, and Google AI Overviews, generating varied question phrasings so results reflect real usage rather than one canned prompt. Beyond simple mentions, it scores sentiment and computes share-of-voice against named competitors, building trend data over time. It's fully open source under the MIT license, self-hostable on your own Supabase instance, and uses a bring-your-own-API-key model — meaning your data never leaves your own infrastructure and there's no markup on model usage.
💬 Our review
The short version: for a genuinely new problem — knowing whether AI assistants are recommending you or your competitors — Lettertrace is about as low-risk a way to start tracking it as exists, because it's free, open, and self-hosted.
Compared to commercial AEO/GEO tools and brand-monitoring suites like Brandwatch or Mention (which bundle AI-visibility tracking into pricier, broader platforms), Lettertrace does one thing and charges nothing for it — the trade-off is you run the infrastructure yourself and pay your own API costs for the underlying model calls, rather than getting a polished SaaS dashboard with support. It's also a young, single-maintainer project, so don't expect the breadth of competitor-tracking or historical benchmarking a funded AEO platform offers. For any team wanting a first, no-cost look at their AI visibility, it's an easy yes; teams already paying for a full brand-monitoring suite that includes AI mentions may not need a second tool for the same signal.
💰 Pricing
📊 Global score
🤖 AI-enriched data
100% gratuit, licence MIT, auto-hébergeable (Supabase). Modèle bring-your-own-key : vous payez uniquement vos propres appels API aux modèles, sans marge Lettertrace.
Pros
Entièrement gratuit et open-source (MIT), zéro coût de licence
Auto-hébergeable, données restant sur votre propre infrastructure
Suit Claude, ChatGPT, Gemini ET Google AI Overviews en un seul outil
Analyse de sentiment et share-of-voice vs concurrents nommés
Modèle bring-your-own-key : pas de marge cachée sur les appels IA
Cons
Nécessite de l'auto-hébergement — pas de SaaS clé en main
Projet jeune, maintenu par un seul développeur à ce stade
Pas de support ni SLA comme sur une suite commerciale
Fonctionnalités de benchmarking concurrentiel plus basiques que les outils AEO payants