Dive Planner
Plan decompression dives with the Bühlmann ZH-L16C algorithm. Configure gradient factors, multiple gases, and get detailed ascent profiles.
Plan Safer Dives with Professional Tools
Decompression dive planning, gas calculations, and blending tools. Built for recreational and technical divers who take safety seriously.
By Divers, For Divers
DiveToolbox was born from a passion for diving and a commitment to safety. We build the tools we wish we'd had.
DiveToolbox is built by active divers who understand the real-world demands of dive planning. Every feature we develop comes from firsthand experience underwater — from recreational reef dives to deep technical expeditions.
Safety is at the core of everything we do. Our decompression algorithms are based on the industry-standard Bühlmann ZH-L16C model with configurable gradient factors, giving you the precision and conservatism controls that professional divers demand.
We believe that powerful dive planning tools should be accessible to every diver, regardless of experience level. That's why DiveToolbox is designed to be intuitive for beginners while offering the advanced features that technical divers need.
Everything You Need for Dive Planning
Professional-grade tools designed for divers who want accurate calculations and safe dive plans.
Gas Calculators
Calculate MOD, EAD, END, and Best Mix instantly. Essential tools for safe nitrox and trimix diving.
Gas Blending
Precise partial pressure calculations for nitrox and trimix blending. Get step-by-step instructions for your target mix.
Unit Conversions
Convert between metric and imperial units effortlessly. Depth, pressure, temperature, volume, and more.
Gradient Factors
Understand and optimize your GF settings. See how different values affect your no-deco limits and decompression requirements.
Successive Dives
Plan multiple dives in sequence with surface intervals. Calculate residual nitrogen from previous dives and determine no-decompression limits for your next dive.
SAC / RMV
Calculate your Surface Air Consumption rate. Input tank specs, depth, and time to determine your personal breathing rate for accurate gas planning.
Rock Bottom
Calculate minimum gas reserves for emergency ascent. Accounts for stressed breathing, buddy sharing, and safety stops to determine your turn pressure.
Why DiveToolbox?
Industry-Standard Algorithms
Using proven Bühlmann ZH-L16C decompression model trusted by technical divers worldwide.
Fast & Responsive
Real-time calculations that update as you type. No waiting, no page reloads.
Works Everywhere
Access your dive planning tools from any device - desktop, tablet, or mobile.
Multilingual
Use the app in your preferred language. Available in multiple languages for divers worldwide.
The Science Behind Your Dive Plans
DiveToolbox uses the Bühlmann ZH-L16C decompression algorithm — the gold standard in dive planning — enhanced with gradient factors for customizable safety margins.
Bühlmann ZH-L16C
Developed at the University of Zurich, this industry-standard algorithm models 16 tissue compartments to calculate safe ascent profiles for air, nitrox, trimix, and heliox dives.
Gradient Factors
GF Low and GF High let you fine-tune conservatism. Choose from 6 presets (30/70 to 50/85) or set custom values to match your experience and dive conditions.
Real-Time Planning
Multi-gas planning, automatic deco switching, CNS/OTU tracking, gas density warnings, and rock-bottom analysis — all updating in real time as you adjust parameters.
Built for All Divers
Whether you're doing your first nitrox dive or planning a trimix decompression dive, we've got you covered.
Recreational Divers
- Quick NDL calculations
- Nitrox best mix finder
- Simple unit conversions
- Easy-to-understand results
Technical Divers
- Multi-gas decompression planning
- Customizable gradient factors
- Trimix blending calculations
- Detailed ascent profiles
Dive Professionals
- Grant temporary access to students
- Professional dive planning accessible to students
- Professional dive planning for courses
- Share dive plans with students
Dive Centers
- Manage instructor and student access
- Centralized team management dashboard
- Access codes for training courses
- Monitor usage across your organization
Dive Planning on Any Device
DiveToolbox is fully responsive — plan your dives on desktop, tablet, or phone with the same powerful features.
Frequently Asked Questions
Everything you need to know about DiveToolbox and dive planning.
What is DiveToolbox?
DiveToolbox is a web-based suite of professional dive planning tools. It includes a decompression dive planner powered by the Bühlmann ZH-L16C algorithm, gas calculators (MOD, EAD, END, Best Mix), nitrox and trimix gas blending calculators, unit converters, SAC rate calculator, and more. It's designed for both recreational and technical divers.
What is the Bühlmann ZH-L16C algorithm?
The Bühlmann ZH-L16C is a decompression algorithm developed by Professor Albert A. Bühlmann at the University of Zurich. It models 16 tissue compartments with different half-times to calculate safe ascent profiles. It's one of the most widely used decompression models and forms the basis of many popular dive computers.
What are gradient factors and how do they work?
Gradient factors (GF) are a way to adjust the conservatism of the Bühlmann algorithm. They consist of two values: GF Low (which controls the depth of the first decompression stop) and GF High (which controls the maximum allowed supersaturation at the surface). Lower values are more conservative. Common settings range from 30/70 (very conservative) to 50/85 (less conservative).
Is DiveToolbox suitable for recreational divers?
Absolutely! DiveToolbox is designed for all experience levels. Recreational divers can use the NDL (No Decompression Limit) calculator, Best Mix finder for nitrox, unit converters, and simple dive planning features. The interface is intuitive and results are easy to understand.
Can I plan trimix and multi-gas dives?
Yes. DiveToolbox supports full multi-gas decompression planning with air, nitrox, trimix, and heliox. You can add multiple bottom gases and deco gases, configure automatic gas switching (on MOD or at first stop), and get detailed ascent profiles with gas consumption analysis.
What are MOD, EAD, and END?
MOD (Maximum Operating Depth) is the deepest depth at which a gas mix can be safely used based on its oxygen content and a maximum PPO₂ limit. EAD (Equivalent Air Depth) converts a nitrox dive to its equivalent depth on air for decompression purposes. END (Equivalent Narcotic Depth) calculates the narcotic effect of a gas mix, especially relevant for trimix diving with helium.
How does the nitrox blending calculator work?
The gas blending calculator uses the partial pressure method to determine exactly how much pure oxygen and air (or helium for trimix) to add to your tank. You enter your current tank pressure and mix, your target pressure and mix, and it provides step-by-step fill instructions with precise pressures for each gas addition.
What languages does DiveToolbox support?
DiveToolbox is available in 7 languages: English, French, German, Italian, Spanish, Russian, and Polish. You can switch languages at any time from the footer of any page, and all tools, labels, and content will update instantly.
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