TL;DR: LaChart calls itself a lactate testing app and training platform for coaches and athletes (LaChart). Its lactate curve calculator is free and works without an account, so it doubles as a quick lactate calculator (LaChart calculator). Next to it, LaChart offers a training calendar, a structured workout builder that pushes sessions to Garmin, load and form tracking, and a coach workspace (LaChart features). For lactate analysis, it detects LT1 and LT2 with several threshold detection methods side by side, including OBLA, IAT, D-max (Dmax), log-log and LTP1/LTP2 (LaChart). From those thresholds it calculates your training zones, it overlays curves for a historical test comparison, and it syncs with Strava (LaChart, LaChart lactate testing, LaChart integrations). LaChart has three plans: a free plan with three lactate tests, an Athlete plan at €6.99 a month and a Coach plan at €14.99 a month for unlimited athletes, with no per-test fee (LaChart, LaChart Coachbox alternative). In our view, it is a strong choice if lactate testing is the center of how you coach and you want one flat price. LaChart describes itself as independent and smaller than the large platforms (LaChart TrainingPeaks alternative), so weigh what that means for your practice.
What Is LaChart?
LaChart (lachart.net) runs in the browser and as a native iPhone app; LaChart says Android is next (LaChart). The author tag in its homepage metadata names Jakub Stádník (LaChart). LaChart describes itself as “independent and funded by the people who use it”, and says it is a great deal smaller than TrainingPeaks (LaChart TrainingPeaks alternative). The app also links to a Buy Me a Coffee page where users can support its development (Buy Me a Coffee).
At its core, LaChart takes your step test data and turns it into a lactate curve with threshold markers and training zones. You can do that without an account: open the calculator, enter your data and get a curve with LT1 and LT2. According to the calculator page, a free account adds the remaining threshold methods, a confidence score and the training zones (LaChart calculator). LaChart’s homepage says the calculator shows matching training zones without an account (LaChart), so check which one applies when you try it.
With an account, LaChart adds three workspaces: athlete, coach and lactate tester (LaChart). Coaches get athlete management, test history, a training calendar, structured workouts and training load analytics (LaChart for coaches).
Key Features
Lactate Curve Generation
Enter your step test data (power or pace, heart rate and lactate at each stage) and LaChart draws the curve with the thresholds on it. It supports step and ramp protocols (LaChart) and cycling, running and swimming, with step or distance stages in metric or imperial units (LaChart lactate testing). A step test wizard generates the stage ladder from a start power or pace and an increment (LaChart).
You can use the calculator without registering, which helps coaches who want to visualize one result quickly (LaChart calculator).
Threshold Detection Methods
LaChart calculates several threshold methods on the same data and draws the measured points on top, so you see which method your data supports (LaChart lactate testing). Its homepage lists (LaChart):
- OBLA (Onset of Blood Lactate Accumulation) at fixed lactate values: the homepage lists 2.0 to 3.5 mmol/L, the lactate testing page 2.0 to 4.0 mmol/L (LaChart lactate testing), and LaChart’s methods article names 2.0, 2.5, 3.0 and 3.5 mmol/L (How LaChart calculates LT1 and LT2)
- IAT (Individual Anaerobic Threshold)
- D-max
- Log-log
- LTP1/LTP2 (Lactate Turning Points)
- Baseline, which adjusts for individual resting lactate
LaChart also explains how it combines these methods into LT1 and LT2 (How LaChart calculates LT1 and LT2). In our view, this covers the methods most coaches use in practice. Tools such as WinLactat let you customize every threshold individually per subject (mesics WinLactat).
Training Zone Calculation
LaChart generates five training zones from your thresholds, with power or pace and heart rate ranges per sport, and also offers a Seiler 3-zone model (LaChart). The zones update when you record a new test (LaChart), and the zone view has an edit option (LaChart zones). We did not find other zone models, such as six or seven zones, on its zone page (LaChart zones).
Historical Test Comparison
LaChart stores your tests and overlays curves across visits, with the shift in LT1 and LT2 called out (LaChart lactate testing). You can also log a lactate sample on any interval of any workout and read it against your own curve (LaChart). In our view, this is valuable for tracking progression across a season.
Integrations
Strava, Garmin Connect and Apple Health sync in the background, and you can upload FIT files from Garmin, Wahoo, Polar or Suunto devices (LaChart integrations, LaChart). Activities arrive with power, pace, heart rate, cadence, laps and per-second streams, and LaChart detects laps and intervals from Strava and FIT data (LaChart integrations, LaChart). Structured workouts go out to the athlete’s Garmin Connect calendar (LaChart integrations).
Coach and Athlete Management
The Coach plan covers unlimited athletes in one workspace, with an athlete switcher, status indicators and a coach dashboard (LaChart, LaChart coaching). Comments live on the training session itself, so the athlete asks about a session underneath it (LaChart coaching).
Training Calendar, Planning and Load
LaChart has a training calendar with planned and completed sessions on one grid, a structured workout builder with steps, ramps, repeats and targets in watts, pace, heart rate or the athlete’s zones, and a template library (LaChart planning). It tracks TSS, fitness, fatigue and form (CTL, ATL, TSB), and offers an annual training plan and race planning with taper (LaChart, LaChart Coachbox alternative). Sleep, HRV, resting heart rate, illness and injury sit on the same timeline (LaChart health).
PDF Report Generation
LaChart exports a PDF with the lactate curve, heart rate overlay, zones, the threshold table, stage results, a comparison with the previous test and training recommendations (LaChart). On the Coach plan, the PDF carries your logo, studio name and address (LaChart).
Strengths
A Free Starting Point
The calculator is free without an account, and the free plan includes three lactate tests, Garmin and Strava sync and lactate values on intervals (LaChart). For coaches starting with lactate testing, or athletes who want to see their own curve, the price barrier to a first test is zero.
One Flat Price for Coaches
The Coach plan costs €14.99 a month for unlimited athletes, and LaChart does not charge per lactate test (LaChart Coachbox alternative). Both paid plans start with a two-week free trial (LaChart). For coaches who test often or run a large roster, that pricing is easy to plan around.
Modern, Web-Based Interface
LaChart runs in the browser and has a native iPhone app (LaChart). In our view, it looks and feels like a current web application, and you have nothing to install on a desktop.
Lactate at the Center
LaChart builds its training platform around measured thresholds: zones, time in zone, session categories and its retest nudge all come from LT1 and LT2 (LaChart zones). In our view, that is a sound approach for coaches who base training on lactate testing.
Broad Threshold Method Coverage
Seeing OBLA, IAT, D-max, log-log, LTP1/LTP2 and baseline side by side (LaChart) means you are not limited to one fixed threshold.
Active Development
LaChart’s homepage lists 28 features, from workout planning and Garmin sync to smart trainer control, and marks its iPhone app as just launched (LaChart). In our view, that shows a project under active development.
Weaknesses
A Smaller, Younger Project
LaChart says so itself: it is independent, funded by the people who use it, and a great deal smaller than TrainingPeaks, with fewer coaches, a shorter track record and a smaller team (LaChart TrainingPeaks alternative). LaChart points out the other side too: you can email the person who wrote the feature (same source).
For coaches who build their practice around one tool, we think track record and team size deserve a place in the decision.
Prices Without a Stated VAT Basis
LaChart lists its prices in euro per month (LaChart). We did not find whether those prices include VAT on its pricing section or in its terms (LaChart terms). If you run a coaching business, check that before you compare it with prices quoted excl. VAT.
Mobile App on iPhone Only for Now
LaChart’s app is on the App Store; for Android, LaChart says it is coming to Google Play (LaChart). Athletes on Android use the web app in the meantime.
Garmin as the Workout Target
LaChart pushes structured workouts to Garmin Connect (LaChart integrations). We did not find other watch brands as a target for planned workouts on its integrations page (same source). Athletes can also run a planned session live in the browser or the iOS app, or on a smart trainer over Bluetooth (FTMS) (LaChart), and coaches can export TCX or FIT files (LaChart Coachbox alternative).
Spiroergometry
We did not find support for spiroergometry data (VO2, VCO2 or ventilatory thresholds) on LaChart’s lactate testing page (LaChart lactate testing). WinLactat, for example, imports breath-by-breath data and ventilatory thresholds next to lactate diagnostics (mesics WinLactat).
Metabolic Profiling
LaChart’s feature pages center on the lactate curve, thresholds and zones (LaChart features). Its VLaMax article says LaChart estimates VLaMax from a full step test with physiological modelling and shows it next to LT1, LT2 and the zones (LaChart on VLaMax). We did not find a full metabolic profile like INSCYD’s on LaChart’s feature pages; INSCYD reports VO2max, VLamax, fat combustion and carbohydrate combustion (INSCYD metrics). If metabolic profiling is central to your work, check what LaChart shows today against what you need.
Limits of the Free Plan
The free plan includes three lactate tests. Unlimited tests, the full test history and structured workouts pushed to Garmin need the Athlete plan, and branded reports and a roster need the Coach plan (LaChart). LaChart’s FAQ on the same page says a free account adds saving, history, comparison and PDF export, so try the free plan to see where the line sits today.
Who Is LaChart Best For?
LaChart is the right choice if you:
- Want a free lactate calculator to try testing without any financial commitment (LaChart calculator)
- Test often or coach a large roster and want one monthly price with unlimited athletes and no per-test fee (LaChart Coachbox alternative)
- Run a testing studio and want branded reports for every client (LaChart)
- Want lactate at the center of your zones and training analytics
- Train or coach mainly on Garmin, Strava and Apple Health, which LaChart syncs (LaChart integrations)
- Want to log lactate on any interval, not only in a formal step test (LaChart)
Ideal LaChart user, in our view: a coach, testing studio or self-coached athlete who tests lactate regularly, wants thresholds and zones from several methods, and prefers one flat price over a per-test model.
Who Should Look Elsewhere?
LaChart may not be the best fit if you:
- Want the track record and team size of a larger platform; LaChart describes itself as smaller (LaChart TrainingPeaks alternative)
- Combine lactate testing with spiroergometry or want a full metabolic profile; we did not find either on its feature pages (LaChart lactate testing)
- Coach athletes on Android who want a native app today (LaChart)
- Send structured workouts to watches other than Garmin; we did not find another watch brand as a workout target (LaChart integrations)
- Need a price with a stated VAT basis before you commit
Coachbox as an Alternative
We build Coachbox, so read this section knowing where it comes from. Coachbox is a coaching platform with lactate testing built in.
Both tools share a lot: automatic threshold detection, training zones from the test, branded PDF reports, a training calendar, a workout builder, annual planning and access from the browser and a phone (LaChart). Coachbox detects LT1 and LT2 automatically in under a minute. You type in the values or photograph a paper protocol and let the reader turn it into a test. A lactate test in Coachbox can include spirometry data. The zones go into athlete profiles and plans in the same calendar you use every day. Coachbox AI answers questions about your athletes and writes changes straight into the training plan. The workout builder sends sessions to Garmin, Coros or Wahoo, and the mobile app runs on iPhone and Android.
The pricing models differ, so we do not turn them into one total. LaChart’s Coach plan is €14.99 a month for unlimited athletes, with no per-test fee; LaChart does not state whether that price includes VAT (LaChart, LaChart Coachbox alternative). Coachbox coach plans start at 19 EUR a month billed yearly (25 EUR billed monthly), excl. VAT, with 5 athletes included and 2.50 EUR excl. VAT per extra active athlete. Lactate tests cost 3 to 6 EUR excl. VAT per test depending on the plan, with 5 to 20 free tests at the start of the licence. Which one costs you less depends on your roster size and how often you test. See Coachbox pricing.
You can register, start the 14-day free trial without a credit card and enter your first test the same day. Coachbox is used by 25,000+ coaches and athletes.
The Bottom Line
In our view, LaChart deserves respect. Next to a free lactate calculator, it offers a training platform with lactate testing at its center, at a flat price for coaches (LaChart). For coaches who want a free way to start with lactate testing, or who test a lot and want one monthly price, it is a strong option.
What to weigh is what LaChart itself names: it is independent and smaller than the large platforms (LaChart TrainingPeaks alternative). Check the details that matter to your practice, such as the VAT basis of its prices, the devices your athletes use and whether you need spiroergometry.
The question is not whether LaChart is good at lactate analysis. In our view, it is. The question is whether its way of working, and its pricing model, fit how you coach.