TL;DR: LaChart is completely free. No subscription, no license fee, no freemium tier, no feature gates. It’s funded through voluntary donations (Buy Me a Coffee) and Google AdSense. That’s genuinely remarkable for a lactate analysis tool with this feature set. But “free” doesn’t mean “zero cost,” and it definitely doesn’t mean “everything you need.” Your time has value, and the hours you spend on manual workflows that an integrated platform would eliminate are a real cost. Here’s how to think about the true economics.
LaChart Pricing: The Simple Answer
LaChart costs EUR 0. That’s the pricing page, the feature comparison, and the enterprise tier all rolled into one number. Every feature is available to every user at no cost:
- Lactate curve generation
- LT1/LT2/LTP1/LTP2/IAT/OBLA threshold detection
- Training zone calculation (5 zones)
- Historical test comparison
- Strava integration
- FIT file upload
- Coach & athlete management
- Training calendar with TSS analytics
- PDF report generation
There are no premium tiers, no feature locks, and no trial periods. You get everything from day one.
How LaChart Stays Free
LaChart is funded through two channels:
- Buy Me a Coffee donations: Voluntary contributions from users who want to support the project
- Google AdSense: Advertising revenue from ads displayed on the platform
This is a common model for independent developer projects. It keeps the barrier to entry at zero, which is great for adoption, but it creates a fundamentally different economic relationship than subscription software.
When you pay for software, you’re a customer. The company has a financial obligation to keep you happy, maintain the product, and provide support. When you use donation-funded software, you’re a beneficiary. The developer maintains the project because they want to, not because they’re contractually obligated to.
This distinction matters more than most people think.
The True Cost of “Free”
Free software has costs that don’t show up on an invoice. Let’s walk through them honestly.
Your Time Is Not Free
The biggest hidden cost of LaChart isn’t in the tool itself. It’s in what the tool doesn’t do. After every lactate test, you need to:
- Manually transfer zones to your coaching platform (3-5 minutes per test)
- Export or screenshot reports and send them to athletes via email or messaging (2-3 minutes)
- Update athlete profiles in your separate coaching system (2-3 minutes)
- Cross-reference test history by switching between LaChart and your coaching records (variable)
For a coach running 5 tests per week, that’s roughly 35-55 minutes of admin work that an integrated platform would eliminate. Over a year, that adds up to 30-48 hours of time spent on tasks that software could handle automatically.
What’s your hourly rate? If you value your coaching time at EUR 50-100 per hour, the “free” tool costs you EUR 1,500-4,800 per year in manual workflow time.
No Support Guarantee
When something breaks in LaChart, there’s no support team to contact, no SLA, and no guarantee of a fix timeline. The developer maintains the project voluntarily. A bug might get fixed in a day or might wait weeks.
For individual coaches running occasional tests, this is usually fine. For coaching businesses that depend on reliable testing workflows, the absence of professional support is a risk worth quantifying.
Data Portability Questions
Where does your data live? What happens if LaChart goes offline? Can you export your full test history in a standard format? These are questions that paid platforms answer clearly in their terms of service. With donation-funded projects, the answers may be less defined.
No Branding for Your Business
LaChart’s PDF reports are functional but generic. There’s no option to add your logo, practice name, or custom branding. For coaches who use test reports as a professional deliverable, an unbranded report from a free tool sends a different message than a polished, branded report from a professional platform.
This isn’t about vanity. For coaches charging EUR 50-150 per lactate test, the report is part of the service. A branded, professional report reinforces the value you’re providing.
When Free Is Absolutely Enough
Let’s be honest about when LaChart’s price point is exactly right:
For Students and Learners
If you’re studying sport science and want to practice lactate curve analysis, LaChart is perfect. Zero financial risk, solid methodology, and you learn the fundamentals without committing to expensive software.
For Occasional Self-Testers
Athletes who run their own lactate tests a few times per year and just want to see their curve and zones don’t need a coaching platform. LaChart does exactly what they need.
For Budget-Constrained New Coaches
Coaches just starting their practice, with fewer than 5 athletes and tight finances, can use LaChart for testing while investing their limited budget elsewhere. It’s a smart way to offer lactate testing before your business can justify a paid tool.
For Quick One-Off Analysis
Sometimes you just need to plot a curve quickly. Maybe you’re at a conference, someone shares test data, and you want to visualize it on the spot. LaChart’s no-registration calculator is perfect for this.
When Free Isn’t Enough
The tipping point usually comes when one or more of these become true:
You Manage More Than 5-10 Athletes
The manual transfer overhead scales linearly with athlete count. Five athletes? Manageable. Twenty? You’re spending hours on admin that software should handle.
You Charge for Testing Services
When athletes pay for your testing service, they expect professional output. Branded reports, integrated zone updates, and seamless follow-up are part of the value proposition. A free tool with generic output can undermine the professional impression you’re building.
You Need Testing Connected to Coaching
If you’re also the coach (not just the tester), having zones automatically flow into training plans, athlete profiles, and workout prescriptions saves real time and prevents errors from manual data entry.
Reliability Becomes Business-Critical
When your coaching business depends on being able to run tests on schedule and deliver results promptly, you need a tool backed by a company with resources, support, and a commitment to uptime.
How Coachbox Pricing Compares
Coachbox offers two paths for lactate testing, depending on whether you need the full coaching platform or just the testing module.
Option 1: Coaching Plans (for coaches who also test)
Lactate testing is built into the Coachbox coaching subscription. Each plan includes free tests monthly, with additional tests at per-test pricing:
| Plan | Monthly Price | Free Tests/Month | Per Extra Test |
|---|---|---|---|
| Start | See coachbox.io | 5 | EUR 6 |
| Build | See coachbox.io | 10 | EUR 5 |
| Peak | See coachbox.io | 15 | EUR 4 |
| Prime | See coachbox.io | 20 | EUR 3 |
On top of lactate testing, you get the full coaching platform: training planning, athlete communication, calendars, annual planning, analytics, device sync (Garmin, Wahoo, Polar), and 25,000+ users worth of platform maturity.
Option 2: Lactate Module Standalone (for labs and occasional testers)
For sports labs, physiologists, and practitioners who don’t need a full coaching platform, there’s a standalone Lactate Module with a monthly subscription plus one-time test bundles (50, 100, or 250 tests).
What You Get for the Money
| Feature | LaChart (Free) | Coachbox |
|---|---|---|
| Lactate curve analysis | Yes | Yes, AI-powered |
| Threshold detection | OBLA, IAT, Dmax, Log-log, LTP | Automatic LT1/LT2 + multiple methods |
| Zone calculation | 5 zones | Fully customizable zone models |
| Historical comparison | Yes | Yes, integrated with athlete profile |
| PDF reports | Basic, unbranded | Professional, custom-branded |
| Spiroergometry | No | Yes |
| Training planning | No | Full planning and scheduling |
| Workout builder | No | Yes |
| Annual planning | No | Yes |
| Athlete communication | No | In-app messaging |
| Calendar integration | View only (via Strava) | Full planning calendar |
| Device sync | Strava only | Garmin, Wahoo, Polar, Strava, and more |
| Support | Community/voluntary | Professional support included |
| Custom branding | No | Yes |
| Platform reliability | One developer, donation-funded | Company-backed, 25,000+ users |
The Math: When Does Paying Make Sense?
Let’s run some scenarios to see when the upgrade from free to paid becomes financially rational.
Scenario 1: The New Coach (5 athletes, 3 tests/month)
- LaChart cost: EUR 0
- Time spent on manual workflows: ~1.5 hours/month (EUR 75-150 at typical coaching rates)
- Coachbox Start plan: Covers 5 free tests, includes full coaching platform
- Break-even consideration: If the coaching platform replaces another tool you’re paying for, Coachbox may actually save money overall
Verdict: LaChart is fine here. The time cost is manageable, and the coaching practice is still small. But if you’re already paying for a separate coaching platform, consolidating into Coachbox could save money.
Scenario 2: The Growing Coach (15 athletes, 10 tests/month)
- LaChart cost: EUR 0
- Time spent on manual workflows: ~5 hours/month (EUR 250-500 at typical coaching rates)
- Coachbox Build plan: Covers 10 free tests, includes full coaching platform
- Net savings: Even after the subscription cost, the time saved on manual workflows and the elimination of a separate coaching platform often puts you ahead
Verdict: This is the tipping point. The manual overhead is significant, and the value of integrated coaching tools is clear. Paying for Coachbox is likely cheaper than the hidden cost of “free.”
Scenario 3: The Established Coach (30+ athletes, 20+ tests/month)
- LaChart cost: EUR 0
- Time spent on manual workflows: ~10+ hours/month (EUR 500-1,000+ at typical coaching rates)
- Coachbox Peak or Prime plan: 15-20 free tests, full platform, lowest per-test rates
- Net savings: Substantial. The time savings alone far exceed the subscription cost
Verdict: At this scale, using a free tool without coaching integration is costing you serious money. The subscription pays for itself many times over.
Tips for Making the Right Decision
Start with LaChart If…
- You’re brand new to lactate testing and want to learn the basics
- You have fewer than 5 athletes and run tests occasionally
- You’re a student or researcher who needs a quick calculator
- Budget is genuinely tight and every euro matters right now
Move to Coachbox When…
- You find yourself spending more than an hour per week on manual data transfer
- You start charging for testing services and need professional reports
- You want test results connected to your coaching workflow automatically
- You need platform reliability for your business operations
- You’re managing enough athletes that the manual overhead is noticeable
Don’t Wait Too Long
One pattern we see often: coaches stick with free tools past the point where they should upgrade, because “free” feels safe and paying feels like a risk. But the accumulated time cost of manual workflows is invisible until you add it up. If you’re spending 5+ hours per month on tasks that an integrated platform would eliminate, you’re not saving money by using a free tool. You’re spending it differently.
The Bottom Line
LaChart’s pricing is its greatest strength. Free means accessible, low-risk, and available to everyone. For the right user, it’s exactly the right price.
But pricing isn’t just what you pay for the tool. It’s what you pay in time, missed professionalism, and workflow friction to work around the tool’s limitations. As your coaching practice grows, the “free” tool can quietly become more expensive than the paid alternative that saves you hours every week.
The best pricing decision depends on where you are today and where you’re headed. LaChart is a great place to start. Just don’t let “free” keep you there longer than it should.