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Dive computer reviews are perfectly organized and consist of fully researched information and ratings of Aeris, Cressi, Mares, Oceanic, Sherwood, Suunto, Tusa, and UWATEC/ScubaPro brands.  In Catalogue Section you may compare any models side-by-side and select dive computer according to your needs! Join thousands of happy customers!


Suunto D4i Dive Computer Lets You Plunging Into The Diving World Without Hassle

Suunto D4i Dive Computer Lets You Plunging Into The Diving World Without Hassle

Suunto D4i dive computer inherited most of the functions of its predecessor D4, but got one function that made it even more attractive to divers! And it is - wireless air integration. It has 3 dive modes - Air, Nitrox and FREEdiving with possibility to set 1 Nitrox mix with FO2 up to 50%. It is recommended dive computer for the every recreational diver, no matter what is the skills level!

General Information
User Interface
Your Review



Suunto D4i dive computer meets not only all the requirements of every recreational diver, but it is suitable for freediving as well, thanx to its dedicated mode. Its excellent menu and display layout allows us feeling comfortable underwater and on surface.

Suunto D4i allows us selecting a range of oxygen concentration in gas mixture from 21% to 50% and set the level of oxygen partial pressure between 0.5 and 1.6 bar. And it supports only 1 Nitrox mix. So, these parameters remain the same as in previous model.

Few more differences in settings - D4i doesn't have RGBM attenuation function and received contrast adjustment of the display. And the main difference from the previous model D4 - it's, of course, possibility to link a wireless transmitter and dive computer, which allows you monitoring air pressure and the amount of remaining air in the cylinder.


Suunto D4i Features Card

Copy this Suunto D4i Features & Alarms Card for your Reference and Share with your friends and buddies!


Suunto D4i - add to the functionality of the "old" D4 the use of transmitter and special software Suunto DM4, integrated with divers-net, and you get a very nice "little brother" of the family updated series D. Five color versions of the design will allow you to pick up your dive computer to suit your personality and style, and the new software will allow to share your dive history and profiles with other divers through the service Movescount.com

Below is the listing of the main differences between Suunto D4i and D4:

  1. different display layout to accomodate air integration;
  2. setting contrast of the display;
  3. functions related to air integration: tank pressure alarms, air time remaining (ATR);
  4. No RGBM attenuation;
  5. Plan Mode set as a dedicated mode (in D4 it is set as a sub-mode of Memory mode);
  6. default sampling rate for freediving - 2 sec (1 sec in D4);
  7. DM4 integrated with Movescount



Benefits of using Suunto D4i dive computer

  • you will be able to track your air consumption with optional wireless transmitter;
  • you will get extra-functions related to air integration that will give you more confidence underwater;
  • you will be an owner of stylish dive computer and wrist watch;
  • you will be able to learn and start diving pretty quick, thanx to Suunto D4i perfect user documentation and user-friendly setup;
  • you can select your own colour scheme of your dive computer;
  • you will have Nitrox dive computer with all necessary functions to dive safely and enjoy every minute of your underwater adventure








User Interface
4 buttons
Dive Modes
Air, Nitrox, FREEdive
Standalone Digital Watch
Suunto RGBM
Number of Gas Mixes
Air, 21% - 50%
0.5 - 1.6 bar
Air Integration
Safety Stop (SS)
Deep Stop (DS)
Conservative Factor
Altitude adjustment
A0/A1/A2 - 0-3000 m
Dive Planner
9-45 m
Logbook Capacity
80 dive hrs with 20 sec sampling rate
Max Operational Depth
100 meters
Backlight duration
ON/OFF/5/10/20/30/60 sec
Sampling Rate
Scuba - 10/20/30/60 sec; FREEdive - 1/2/5 sec
User Replaceable Battery
Data Retention
PC Interface
2 years










Suunto D4i dive computer has 4 control buttons on the interactive control console: MODE, SELECT, UP, DOWN. And they are located at the same positions as in D4. Thanks to well-written user manuals and user-friendly interface - it is very easy to learn all operations and buttons assignments. Programming and retrieving data can be made with short or long pressing on the buttons.
For example, switching between modes (TIME, DIVE, PLAN, MEMORY) can be made by short pressing on MODE button, and for backlight activation - you need to apply longer pressure on MODE button.

Dive computer's display layout may be divided on 3 areas:

  • top area shows current depth, NO-FLY icon, daily alarm icon, diver attantion symbol, etc.
  • middle area shows selected mode, NO-DECO Time (NDC), Total Ascent TIme (TAT), ceiling depth, Air Time Remaining (ATR), notations, etc.
  • bottom area is for condition of the wireless transmitter connection display, time, temperature, max depth, Elapsed Dive Time (EDT), current PO2, OLF%, etc.


Suunto D4i has two bar graphs:

  • tank pressure bar graph (with optional and correctly paired wireless transmitter) located on the left side of the screen;
  • ascent rate bar graph located on the right side of the display


 Suunto D4i dive comuter
Suunto D4i dive computer display and user interface


Display layout is very intuitive, and just by glancing down - I could read it with ease!
During diving to see additional data, I pressed UP/DOWN buttons, and to make a bookmark on my diving profile - I pressed SELECT button.

Suunto D4i, like other Suunto dive computers of D-series, has very nice user interface and this feature really adds to already pleasurable using of this instrument.







Suunto D4i dive computer operates in 4 modes and we set all desirable parameters and alarms for TIME and DIVE modes. At this stage we could also plan our next dive, or check out dive logs:

  1. TIME - settings for standalone digital wrist watch, dual time, alarm, backlight and display contrast;
  2. DIVE - set dive mode (Air, Nitrox, FREEdive), pair wireless transmitter, alarms for tank pressure, depth, dive time, safety factor, altitude, etc.
  3. PLAN - here we plan our consecutive dives and by pressing UP/DOWN buttons I could see allowable NO-DECO times and depths at the range 9-45 meters;
  4. MEMORY - mode for viewing our dive logs and dive history


Suunto D4i Settings Card

Copy this Suunto D4i Settings Card for your Reference and Share with your friends and buddies!


D4i doesn't have integrated digital compass, like D6i and D9tx, but it doesn't diminish its beauty and functionality!







Suunto D4i: Diving With Air & Nitrox

After activation selected dive mode, Suunto D4i does all pre-checks, (it is recommended that we activate dive mode before diving for pre-checks) and if all correctly set for air or nitrox, and battery is fine - we are ready to dive.

Dive computer supports diving with only 1 gas - standard Air - FO2 - 21% or Nitrox - FO2 - 21%-50%. If I set D4i for Nitrox - display shows additional info that is related to this dive mode:

  • FO2 set point;
  • PO2 current level;
  • max operational depth (MOD);
  • oxygen toxicity OLF%


During diving with Air I didn't have those values, mentioned above, on display, of course.

Suunto D4i, like all others Suunto dive computers, have interesting function - Bookmarking. So, if I found need to create a certain profile point - I just pressed SELECT button. At that moment dive computer showed BOOKMARK # on display and that point was recorded into the memory.

D4i will show you main and alternative displays easily accessible by pressing UP/DOWN buttons, as shown in our infographics.


Suunto D4i NO-DECO Diving Card

Copy this Suunto D4i NO-DECO Card for your Reference and Share with your friends and buddies!


As in previous model, this dive computer has reminders for Recommended and Mandatory Safety stops, and possibility to set DEEP Stop to ON/OFF. With DEEP Stop set to ON, D4i will still display Recommended Safety stops if needed. Safety stops are activated if you dive deeper than 10 meters, and the stop reminder pops up if I reached depth zone between 3-6 meters.

If I missed Recommended Safety Stop - I won't have any penalty or decrease in my bottom time or increase in surface intervals.
As a good and safe practice - Mandatory Safety stops must be followed precisely. In addition to this I want to tell that every safety stop reminder is accompanied with audio signal, so it is hard to miss anything.

If you are about diving at altitude - Suunto D4i provides you with manual adjustment of the correct altitude values. It has 3 levels - from 0 meters to 3000 meters, and corresponding programs to these values - A0-A2 (the same as in Suunto D4). To make dive computer more conservative in calculations - I could set appropriate to my current conditions corresponding personal safety factor - P0-P2 (again the same as in Suunto D4).

If I set instrument for Nitrox - all calculations and display layout will reflect data related to this dive mode. And in addition to standard dive data, several other values will be displayed that are related to diving with Nitrox only. And to see them - press UP/DOWN buttons:

  • FO2 set point;
  • current PO2;
  • max depth, related to adjusted Nitrox values;
  • current OLF% (oxygen toxicity level)


If I exceeded No-Decompression Limits (NDLs) – Suunto D4i would activate Decompression mode. All data that I will get after that is related to Decompression mode. During decompression I may be prompted to complete one or few decompression stops at a range of depths.

This Suunto computer (as well as other Suunto dive computers) has Continuous Decompression feature that allows divers performing decompression within the certain range of depths, so called Decompression range. It starts from the ‘floor’ (deepest depth where deco stop time won’t increase) to the ‘ceiling’ (shallowest depth) and decompression is done between them. This feature is similar and exclusive to all Suunto scuba dive computers.

During decompression stage Suunto D4i displays following data that is most important to us at this moment:

  • Ascent Time in minutes (total time to surface, including time to reach the correct ceiling, time to stop at the ceiling, Mandatory Safety Stop (if any), time to surface after ceiling);
  • ceiling depth and correct ceiling range;
  • guiding arrows (for your correct ceiling zone and depth)


You need to follow dive computer guidance to complete decompression without problems. Suunto D4i manages deco mode perfectly and display itself, and all process is very intuitive and easy to understand. During decompression, Total Ascent Time decreasing, and ceiling depth goes up. Your deco stage ends and you may resurface only when ASC TIME, CEILING, and STOP symbols are not displayed anymore.

If diver, by some reason, ascend above the correct decompression ceiling, D4i will give an audio alarm with DOWN Arrow, current depth and ceiling depth values, and Error symbol. It means that diver has only 3 minutes to correct position and move to exact ceiling depth displayed or below the ceiling.

If you violate the decompression just out of curiosity or your oddity – scuba dive computer will activate permanent Error Mode and will work as a depth gauge and timer only and you must not dive for at least 48 hours.


Suunto D4i: FREEdiving

This dive mode makes Suunto D4i very attractive instrument for freedivers and spearfishing. In this mode scuba dive computer operates as a depth gauge and timer only, it doesn't provide any deco and wireless air integration information, and doesn't track diver's ascent speed.

In this mode Suunto D4i has 2 specific alarms that can be set only for freediving – one of them is Depth Notify and Surface Time Notify alarms:

  1. Depth Notify alarm goes on when you reached certain depth that you set before diving.
  2. Surface Time Notify alarm reminds you when time on surface between you previous dive and next dive elapsed.

In Freedive Mode, this Suunto computer displays following information:

  • total dive time in minutes and seconds;
  • max depth reached;
  • current depth;
  • applicable notations


Freediving Mode has function, called Day History. After diving you may access this history in SURFACE mode and view following information:

  • average depth of all dives that day;
  • time and deepest depth reached during a day;
  • longest dive;
  • total number of dives and total dive time during a day session


If you start new dive in Freedive Mode next day – Suunto D4i will reset all freediving day history and start all from the beginning.

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When dive computer senses depth of 1.2 meters (in Scuba mode) or 0.5 meters (in FREEdive mode), Suunto D4i turns SURFACE display and shows:

  • max and current depths;
  • dive time;
  • surface interval time;
  • NO-FLY symbol;
  • diver attention symbol (if conditions exist);
  • values, related to diving with Nitrox, etc.


At this stage we may be interested in following modes:

  • PLAN NoDEC - dive planner for range 9-45 meters. Using Dive Planner I could check out available depths and bottom times, according to nitrogen and oxygen intake from previous dives and all dive history for the past 4 days;
  • MEM History holds maximum 999 dives and 999 diving hours for SCUBA mode, and 999 dives and 99 hours 59 min for FREEdive mode;
  • MEM Logbook can hold about 80 dive hours with 20 sec sampling rate, and consists of 3 pages with detailed information and graphics of diving profile;
  • PC interface - using DM4 (dive manager) software it is possible to download and organize all dive data from Suunto D4i to PC


If during first 5 minutes after resurfacing I submerge, Suunto D4i will count this dive as a continuation of the previous dive.







Suunto D4i: What Divers Say


  • recommended dive computer for every recreational diver, regardless of skill level;
  • easy to read and intuitive display, very user-friendly interface and documentation;
  • perfect dive computer for multiple dives in a day;
  • easy to press buttons;
  • excellent operational efficiency;
  • no problems with wireless;
  • perfectly sits on the wrist



  • no user replaceable battery;
  • no battery "hot swap" or data retention function


Suunto D4i inherited majority of functions from its predecessor D4 plus got wireless air integration with support of 1 transmitter. It has slightly different set of menus and options, corresponding to 4th operating mode. In D4i PLAN and MEMORY modes are separated, but in D4 PLAN mode included into MEMORY mode. Also D4i doesn't have RGBM Attenuation feature, like D4. And now we may adjust display contrast in Suunto D4i.

Dive computer operating manual is easy to read and follow, so even if Suunto D4i is your first dive computer ever - you won't have any troubles to learn this instrument. Documentation is structured very well, like in all other Suunto dive computers.

This dive computer has high level of being customized for different diving situations and it is another benefit, because it will give the flexibility of using it in air, nitrox, and freediving, and at the same time it provides us with all measures to keep us safe! All settings are logically structured, and with easy access diver can program any setting quickly.

With possibility of contrast adjustment and strong backlight - display is clearly seen under water and on surface even in sunny day. Audio alarms are loud enough to grab diver's attention.

Wireless works well - I had very short disconnections couple of times, but it was picked up back straight away, so I don't consider those incidents as downsides of this model, because it may happen with every wireless air-integrated dive computer!


Suunto D4i dive computerSuunto D4i

Dive-Computer-Wizard Rating
golden star golden star golden star golden star half star


With its reliability in service and operations Suunto D4i can definitely be recommended dive computer for every recreational diver and beginners in diving who require multitasking instrument for diving and stylish digital standalone watch!



Add comment
Philip, 18 October 2013 07:17
Overpriced Dive Computer & Transmitter

Suunto D4i is very well designed and setup dive computer, but it is overpriced as a whole system with transmitter and PC interface cable, in my opinion. Because you will be paying close to USD1000 for the whole pack, plus extra-money for battery replacement every 1.5-2 years, as this dive watch computer doesn't have user battery replacement option.

Max, 1 August 2013 17:17
Suunto D4i - Stable Wireless

Suunto D4i is a great dive computer for any recreational and freediver. Perfect user docs and interface, intuitive menus and all operations. Wireless works steady - I haven't lost it even for 2 secs for all 250 dives I logged on D4i. I love Suunto D4i so much, that I got over even the lack of user replaceable battery!

Steve, 22 May 2013 07:23
Reliable Wrist Style Diving Watch Computer

Suunto D4i wrist diving watch computer is a reliable device with easy to read display.

It works absolutely perfect in warm and cold waters. I always preferred a wrist style dive computer and it didn't spoil my expectations for more than 50 dives logged!

I especially like the wireless air integration, that works seamlessly with no troubles at all!

Suunto D4i works great as a digital wrist watch as well and with alternate time settings I could set time zone for area I'm about to go.

QMan, 18 May 2013 06:44
Smooth Performance - Great For Recreational Diving

I've been using Suunto D4i for less than 1 year, diving recreationally and sometimes chasing fish with my spear gun. I've chosen D4i as a replacement for my ZOOP dive computer.

Suunto D4i has never failed me - wireless is always perfect, display info is easy viewable at any depth and angle. It inherited style of perfect written user documentation, like all Suunto dive computers have. I can wear it onshore, in my office, and daily activities, as D4i has integrated digital wrist watch functions - it is not bulky at all.

I can surely recommend Suunto D4i to any recreational and freediver.

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