CSS Calculator Pro vs LaChart
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
CSS Calculator Pro
This application helps swimmers learn and calculate their critical swim speed and sprint distance index. It also allows users to predict their race times based on their performance metrics.
- Learn critical swim speed test
- Calculate critical swim speed
- Calculate sprint distance index
- Predict race time
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With this simple app you will - Learn how to perform critical swim speed test - Calculate your critical swim speed and sprint distance index - Predict your race time
LaChart
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LaChart is a professional lactate testing and athlete performance tracking app designed for coaches and endurance athletes. LACTATE TESTING • Conduct step tests and record blood lactate values in real time • Connect Bluetooth heart rate monitors for live HR tracking • Automatic lactate curve calculation with LT1 and LT2 threshold detection • Manual threshold override for custom coaching adjustments TRAINING ZONES • Automatic zone calculation based on lactate thresholds • Support for cycling (power/watts), running (pace) and swimming • Metric and imperial unit support ATHLETE MANAGEMENT • Manage multiple athletes from a single coach account • Track progress across multiple tests over time • Compare test results and monitor fitness development REPORTS & SHARING • Generate professional PDF reports for each test • Send reports directly to athletes via email • Visual lactate curve charts included in every report DESIGNED FOR PROFESSIONALS LaChart is built for sports scientists, coaches and serious athletes who need accurate, data-driven insights to optimize training load and performance.
Screenshots
Verdict
The clearest difference is iOS requirement: CSS Calculator Pro at 8.1 against LaChart's 15.0. On price, update cadence, ads and in-app purchases there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
CSS Calculator Pro ships an update every 2 weeks, LaChart every 9 days. The most recent releases landed on October 8, 2026 and October 11, 2026 respectively.
| Parameter | CSS Calculator Pro | LaChart |
|---|---|---|
| Price | Free | Free |
| Positive reviews | 50.0% of reviews | — |
| Update frequency | Every 2 weeks | Every 9 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 8.1 — better | 15.0 |
| Further details — not scored | ||
| Size | 2 MB | 226 MB |
| Age rating | 4+ | 4+ |
| Developer | Alexey Ovod | Jakub Stadnik |
In-app purchases
CSS Calculator Pro
No in-app purchases
LaChart
No in-app purchases
Questions
Is CSS Calculator Pro free?
Is LaChart free?
Do CSS Calculator Pro or LaChart have ads?
Which is updated more often, CSS Calculator Pro or LaChart?
Other comparisons
