Meals in plain language
Say “oatmeal with banana and peanut butter” — your AI estimates calories and macros, fiber, total sugar and caffeine included, and logs it. No database search.
MacroFactor alternative
MacroFactor doesn't publish one you can connect — so you can't log your MacroFactor diary from Claude or ChatGPT. Nutrition MCP does the same job by conversation, and it's free and open source.
The short answer
The Model Context Protocol (MCP) is the open standard that lets AI assistants like Claude and ChatGPT connect to outside tools. MacroFactor doesn't publish a public MCP server, so there's no official way to log food to your MacroFactor diary from your AI. If you searched for “MacroFactor MCP” or “connect MacroFactor to Claude,” what you're really after is a nutrition tracker that lives inside your AI — that's exactly what Nutrition MCP is.
What you get instead
Say “oatmeal with banana and peanut butter” — your AI estimates calories and macros, fiber, total sugar and caffeine included, and logs it. No database search.
Send a product barcode and pull the label macros from Open Food Facts — fiber and sugar too, where the label lists them. Free for everyone, with no subscription.
Log body weight in kg or lb, set calorie, macro, fiber, sugar, caffeine, and water goals — fiber a target to reach, sugar and caffeine limits to stay under — and track trends toward a goal weight. Alcohol tracking is there too, opt-in and off unless you turn it on.
Ask for daily totals, weekly trends, streaks, and recurring meal patterns — right in the chat.
Import your meal history from another app's CSV export — parsed in your browser, not by the AI. Take everything back out whenever you want: one ZIP with your meals, water, weight, goals and profile, plus your account record, usage telemetry and connected apps, as CSV files. Meals are the only part that can be imported back in for now. Or delete your account, just as easily.
MIT-licensed and self-hostable — no ads, no paywall, no upsell. Audit the code or run your own instance.
MacroFactor vs. Nutrition MCP
MacroFactor's adaptive TDEE coaching is genuinely good. If you mainly want fast, free macro logging inside your AI, Nutrition MCP is a simpler, no-cost fit.
Also compared: MyFitnessPal vs. Nutrition MCP · Cronometer vs. Nutrition MCP · Lose It! vs. Nutrition MCP · Yazio vs. Nutrition MCP · Lifesum vs. Nutrition MCP
Moving from MacroFactor
MacroFactor's pitch is its algorithm: it watches your logged intake and weight and quietly recalculates your calorie and macro targets each week — genuinely clever, adaptive coaching from the Stronger By Science team. That coaching is the product, which is why it's subscription-only.
Nutrition MCP doesn't run a coaching algorithm — but because you're already inside an AI assistant, you can just ask. “Given my last three weeks, should I adjust my calories?” gets your AI's reading of your own logged numbers on demand — an estimate to weigh, not dietary advice. It's a different model: analysis when you want it, conversationally, instead of a fixed weekly recalculation — and it's free.
The honest trade-off is discipline versus flexibility. MacroFactor's weekly recalculation happens whether or not you think to ask, which keeps you honest; the conversational model only adjusts when you prompt it. If you want a hands-off algorithm steering your numbers, MacroFactor is worth the subscription. If you'd rather log for free and pull analysis when you care, this fits better.
Your MacroFactor history
Ask to import and an importer opens right in the chat: pick your export, map the columns, preview what will be added, then confirm. The file is read in your browser — the AI never sees the rows. In clients without in-chat panels, paste your export instead.
What you'd be leaving is the algorithm, not the data. Ask to import and an importer panel opens in the chat: you choose your MacroFactor CSV export, it's parsed in your browser, the columns it recognises are mapped for you, and you confirm a preview before anything is written. The rows never pass through the AI, so nothing gets mistranscribed on the way in.
MacroFactor's export is recognised by name — its serving-size column is the giveaway — and its date, food, meal, calorie, and macro columns map themselves, fiber, total sugar, and caffeine included where the file carries them. If your export reports energy in kilojoules rather than kilocalories, that's converted rather than stored 4.184x too high. Because a column simply headed “Calories” can hold either unit, the unit is offered as a control next to a worked example from your own first row, so you confirm it instead of trusting a guess that would silently inflate every day.
That history is immediately useful rather than just archived. Once weeks of intake and weight are in, you can ask the question MacroFactor's algorithm answered on a schedule — “given the last three weeks, should I adjust my calories?” — and get your AI's reading of your own numbers on demand — an estimate, not dietary advice. A second import of the same file changes nothing, since each row carries a content fingerprint and repeats come back reported as already logged, as long as your timezone hasn't changed in between.
How to switch
Works with any MCP client that supports OAuth 2.0 with PKCE. On first connect you create an account with Google or an email and password.
Using ChatGPT or another client instead? The full install guide covers ChatGPT, Cursor, VS Code, Claude Code, and more.
FAQ
Not an official one. MacroFactor doesn't publish a public Model Context Protocol (MCP) server, so there's no official way to log to your MacroFactor diary from Claude, ChatGPT, or other MCP clients. Some unofficial, community-built servers exist; they aren't made or supported by MacroFactor. Nutrition MCP is different: a free, open-source tracker built as an MCP server from the ground up, with its own account, that can import your MacroFactor CSV export.
There is no official MacroFactor connector for Claude, because MacroFactor publishes no public MCP server. One option is Nutrition MCP, a free MCP server listed in the Claude directory: open it at https://claude.ai/directory/your-listing, click Connect, sign in, and start logging by conversation.
Not automatically. MacroFactor's weekly, algorithmic recalculation is its paid core feature. With Nutrition MCP you ask — “based on my last three weeks of intake and weight, should I adjust my calories?” — and your AI reasons through it on demand, rather than a fixed weekly update.
Yes. Nutrition MCP is completely free and open source, with no trial-then-pay and no free-tier limits — unlike MacroFactor, which has no free tier and requires a subscription after its trial. You need an AI app that supports MCP, such as Claude or ChatGPT, and a free Nutrition MCP account, which you create with Google or an email and password the first time you connect.
If you want to track calories, macros — fiber, total sugar, and caffeine included — water, and weight without opening a separate app or searching a food database, yes. Instead of tapping through a database, you describe what you ate in plain language, send a photo, or scan a barcode, and your AI logs it — completely free and open source.
Yes. Ask to import and an importer opens in the chat: you pick your MacroFactor CSV export, it's parsed in your browser rather than read by the AI, and you confirm a preview before anything is written. MacroFactor's export is recognised by name — the date, food, meal, calories, protein, carbs, and fat map themselves, along with fiber, total sugar, and caffeine when the file has them — and if it reports energy in kilojoules that's converted to kilocalories once you confirm the unit next to an example from your own file. Re-importing the same file creates no duplicates as long as your timezone hasn't changed in between. In clients without in-chat panels you can paste your export instead.
Not when the importer opens. It parses the CSV in your browser and shows you what will be added before anything is written: how many meals, the calorie total, anything it had to flag, and the rows themselves — a long file lists the first of them plus a count of the rest rather than every line. Only the rows you confirm are sent, and they go as structured data rather than through the AI's reply, so no row can be mistyped or invented in transit. Each row also carries a content fingerprint, so running the same file again reports those meals as already logged instead of duplicating them, as long as your timezone hasn't changed in between. If your client can't display in-chat panels, the fallback is to paste the export — the AI does read it on that path, so prefer the importer when you have the choice.
Yes. Nutrition MCP is completely free and open source, with no subscription — whereas MacroFactor requires a paid subscription after its free trial. You need an AI app that supports MCP, such as Claude or ChatGPT, and a free Nutrition MCP account, which you create with Google or an email and password the first time you connect.
Free and open source — no MacroFactor account, no app to open.
MacroFactor is a trademark of its respective owner. Nutrition MCP is an independent, open-source project and is not affiliated with, endorsed by, or sponsored by MacroFactor. Comparisons reflect publicly available information at the time of writing and may change.