Keto carb limit calculator

The path is pure deterministic arithmetic with no network calls and no random seed, so browser widgets and prepaid API clients return identical JSON every time. The free browser tool matches the paid automation contract at $0.002 per successful API item.

What the keto carb limit measures and which inputs you need

Maximum daily net carbohydrates are the upper gram budget of digestible carbohydrate that a ketogenic-style plan still treats as compatible with staying under a chosen threshold. Instead it answers the planning question first: how many net carbohydrate grams per day should you allow before meals are even logged. Nutrition labels often list total carbohydrate and fiber; net carbs in everyday planning language mean total carbohydrate minus fiber (and sometimes sugar alcohols), but this endpoint does not parse a food diary. Send daily_calories as a positive finite number in kilocalories per day; aliases calories, kcal, energy_kcal, and calorie_intake are accepted. Optionally send carb_percent as the maximum share of energy from net carbs, typically near five percent on strict keto macros, with aliases carbs_percent, carb_pct, and percent_carbs; when omitted the engine uses five. Optionally send threshold_g as an absolute ceiling in grams per day, with aliases max_carbs_g, net_carb_cap, absolute_cap_g, and carb_cap_g; when omitted the engine uses fifty grams, a common liberal ketogenic cap, while twenty grams models a stricter therapeutic-style ceiling. The engine multiplies daily calories by carb percent over one hundred to obtain carb kilocalories, divides by four to obtain percent-based net carb grams, then returns the minimum of that value and threshold_g as max_net_carbs_g. If daily calories are missing, zero, or negative the request fails with invalid_input. Identical inputs always yield identical JSON because the algorithm never touches the network, a model, a clock, or a random generator.

Reading the response fields and common pitfalls

Do not treat the result as a medical prescription: people with diabetes, epilepsy protocols, pregnancy, or other clinical constraints need professional guidance. Extremely large calorie or threshold inputs above the published isolate safety caps are rejected. On success the response echoes daily_calories, carb_percent, and threshold_g so clients can confirm the bounds that were applied. The headline number is max_net_carbs_g in grams per day, which is always the lesser of the percent-based path and the absolute threshold. The field percent_based_net_carbs_g shows the calorie-percent path alone so dashboards can explain why a high-calorie day might still be limited by the threshold, or why a low-calorie day hits the percent bound first. carb_kcal is the energy allotted to net carbs from the percent path before dividing by four kilocalories per gram. limiting_factor is either percent or threshold depending on which bound produced the final maximum, which is useful for coaching copy that says “your calorie budget already keeps you under fifty grams” versus “your absolute keto ceiling is the binding constraint.” unit is always g/day, kcal_per_gram_carb is always four, formula restates the min equation, and method is always min_percent_and_threshold so downstream code can branch without sniffing shapes. Pair this ceiling with your own food logger that subtracts fiber to score net carbs against max_net_carbs_g on the client.

API usage, pricing, coaching workflows, and practical limits

Send a JSON body with required daily_calories (or an alias) and optional carb_percent and threshold_g. Use the prepaid API when a wellness SaaS, telehealth intake form, fitness coach dashboard, or calorie-tracking pipeline needs a stable contract under KIT balance at $0.002 per successful item; validation failures never consume balance after the engine rejects the request. Authors shipping SDKs can map max_net_carbs_g and limiting_factor into dashboard cards and export CSV columns labeled percent path and absolute ceiling—the same numbers coaches write by hand when they apply five percent of calories and a twenty-to-fifty gram cap on paper.