Tide Tool 2.2

Tide Computation Software
for Palm Handhelds 

Download Tide Tool 
Read the FAQ, Luke 
Program Instructions
Receive update notifications
Locations List
How People Use Tide Tool
Links to other tide software and info

    Ce logiciel est disponible en version française.
Why French?

Page last updated March 1, 2007

Tide Tool is frozen code and has not been maintained since 2007.  
But I like the user quotes so am leaving this page up.

A beta version of Tide Tool is now available to incorporate the U.S./Canada Daylight Savings Time change and recent NOAA tide data.

Tide Tool is a freeware program to compute tides and currents worldwide. It also provides some sun and moon data.


  • Palm handheld computer. (All models. Some pre-1998 units, like the Pilot 1000 and Pilot 5000, and PalmPilot Personals running the 1.0 OS, require an upgrade; see the FAQ.)
  • Or the Handspring Visor, or any other compatible device running the PalmOS. 

Features in Tide Tool 2.2: (New 2.2 features in bold; other new version 2 features in italics.

  • Computes tides and currents from a worldwide database of almost 7000 locations.  Many locations in Great Britain have been restored.
  • Graphical or tabular display of tides and currents.
  • Tap the graph to get a prediction for a specific time and date.
  • Covers years 1998 to 2031
  • User-selectable units of height and speed
  • Displays times of sunrise/sunset, moonrise/moonset and moon phases
  • Displays in color (or grayscale) on devices that support it, under Palm OS 3.0 or later
  • All regional databases can be loaded; user can enable just those needed
  • Program and data can be beamed.
  • Program and/or data may be placed in expansion memory.
  • The software and website are available in a French version.
  • Tidal coefficients are displayed for French Atlantic ports.
  • A tide level guide, at a level selected by the user, may be displayed in the graph and table. 
  • Runs on Palm OS through version 5.3.

Other improvements from version 1:

  • Major speed improvements (implemented by Jeff Dairiki).
  • Now using the XTide 2.6 database. Many new places have been added, particularly in the U.S., Great Britain, Norway, Japan, Canada, Alaska, New Zealand, Pacific Islands and Australia. German data is improved. Some database files have therefore gotten a lot larger, even though they are better compressed.
  • Secondary, or offset, locations (relative to reference stations) are now incorporated in the database. No, you can't enter them, but you can contribute them to the XTide database and they will eventually get in.

How People Use Tide Tool:

Got an interesting use for Tide Tool?  Please let me know.

  • From the Bay of Fundy:  "We do have large changes in tides. We also have the Reversing Falls here in town. Visitors of course want to know when to see the reversing. So it is handy to have the tides on my Pilot."
  • From Hawaii: "I'm a minister and perform weddings on Maui. Tide Tool allows planning of beach ceremony locations and scheduling of sunset weddings. And it looks major cool to whip out the Palm Pilot."
  • From British Columbia: I often go down to the ocean to pick up critters to feed to my girlfriend's salt water fish, and it was constantly hit and miss. I found your program and loaded it onto her Clie, and bam, wouldn't you know it, in a few hours would be a super low tide, just a few blocks from my home in Victoria. Incredible! On that trip I found a shield backed kelp crab (had never seen one before in my life), a few wonderful looking eels, and some amazing shrimp that almost glowed in the dark.
  • From South Africa: "I am the Station Commander of National Sea Rescue Institute, Station Six, Port Elizabeth, South Africa. As a volunteer organisation we do not usually have the luxury of having a tide table booklet on hand when an emergency call comes in, and so, I find Tide Tool invaluable!" (Always check against reliable tide tables when safety of life or property is at stake. -WB)
  • From San Francisco Bay:  "I sail a Nonsuch 33 on San Francisco Bay and your program is easier and more convenient than the local chart books. Tide Tool has become a permanent addition to my PalmPilot." - Jeff Hawkins, designer of the PalmPilot and Handspring Visor
  • From Alaska: "My husband and I run an air taxi service out of Kodiak.  We use Tide Tool to help us schedule our float plane flights and our bear viewing tours, both of which are tide dependent.:
  • From Papua New Guinea: " I was managing a project in Irian Jaya (Papua) and we ran 8 boats used to transport ± 75 people per day. We had up to 6 meter tides and everything had to be scheduled around tides."
  •   From Louisiana: I work at a Marine Research Center. We have monitoring stations in place around the coast, and at least one of them is in very shallow water. Since I use a Palm for communicating with several of the weather and water instruments, I always have it with me. Tide Tool can save me from sitting on the little instrument platform with my boat sitting in the mud, waiting for the tide to come up.
  • From Colorado: "My great-uncle, after whom I was named, just built a house on the inter-coastal waterway in Texas. I check this tool daily from Colorado and dream of buying the lot next to his after I retire"
  • From Alaska: "I am a Tlingit Indian raised in Southeast Alaska. Tlingits have been around Southeast Alaska for about 8000 years living off the sea.  I use
    Tide Tool to help me know the tides for fishing and subsistence."
  • From South Africa: "I like to fish and having the tides helps.  Also I'm a pagan who uses the moon in ceremonies, so having the moon phases is nice, too."
  • From New York:  "I coach the rowing crew at the U.S. Military Academy at West Point and I thought the program would be really convenient for when I'm planning the training."
  • From Georgia: "I live in Athens, Georgia, USA, which is totally landlocked. However, my mother lives on Huspah Creek in Sheldon, SC. My little boy, age 2, misses his grandmother (as do I). So once a day we sit in his room and bring up Tide Tool so he can see how high the water is at Gran's house."
  • From Brazil: You are helping people here in Brazil, to enjoy the beach on 4WD drive cars, safely.
  • From Washington: "I am a volunteer fireman. Our department has a fire Rescue boat and it's helpful to know what the tides are doing when we go out on a rescue mission."
  •   From New York City: "We use it in our work in the Coast Guard Auxiliary in NY Harbor, to see what's happening with tides and currents for the boats we are helping out on our patrols. As a watchstander at CG Station NY, it is a great help when I get asked the tide at various locations."
  • From New Zealand: "I am involved in land & marine Search and Rescue. I have found Tide Tool to be an excellent resource for tides, sun rise sun sets etc."
  • From California: "My friends and I are an eclectic bunch of overgrown kids who are fond of single-malt Scotch and building sand castles.  I intend to calculate the estimated time of destruction of the completed castle. We are always being asked if we will finish our constructions before the tide takes it. (Of course, we always do. By definition - when the tides comes in we're done.)"
  • From Canada:  "I am a helicopter pilot on the west coast of Canada and I have to take people out to the bush so they can "cruise" the timber (assess the amount and value of a stand of trees).  Quite often I use the ocean shoreline to
    drop them off and pick them up.  I work an area from Seattle to Alaska and it is very hard to hard to keep track of tides without your program."
  • From California:  " I'm a Tugboat operator on San Francisco Bay. I use your program virtually every day at work.  I also use it for sailboat racing here on
    the Bay."
  • From Scotland: I do work with the Fife Ranger Service on the Eden Estuary Nature Reserve which is subject to rapidly rising tides which can, and do leave visitors stranded. Your version 2.0 of the program is accurate to within 3 minutes at my location and has enabled us to be onsite at the correct times to guide people back to safety.
  • From Oregon:  "I am a Paramedic on the Central Oregon Coast. We frequently have surfers, beachcombers, rock climbers and fishermen get into trouble and require rescuing.  I use Tide Tool to determine where the tide is at and how long we have to make the rescue."
  • From Florida: "As the yakmaster for the South Florida Bush Paddlers Association I use Tide Tool to plan and execute trips. There's nothing worse than paddling for miles only to find that the mangrove creek you were headed for is dry. Many a depressing trip has been saved by a reroute spurred by Tide Tool."
  • From the Marshall Islands: "I am the Bikini Atoll Dive Program manager, which necessitates me needing to know the tides on a daily basis. I also dive quite a bit in Majuro Atoll, the capital of the Marshalls."
  • From Maine:  "As the tide comes in through an inlet near Blue Hill Harbor it creates a rapids as if in a river.  Two hours before a certain height of high tide, the inrushing current forms a standing wave.  It is sometimes over 6 ft tall and stands in one place, so you can surf a kayak or a surfboard indefinitely because the wave isn't going anywhere." (See photo)
  • From France: "I find Tide Tool very useful as a WW II tour guide in Normandy dealing with the liberation."
  • From San Francisco: "I am with a group of swimmers called the Sunrisers. We swim in the San Francisco Bay every day of the year. There are massive currents here coming through the Golden Gate - up to 6 or 7 knots going one way or the other. And yes, the water is cold - 52 degrees this morning. You can imagine that the Tide Tool is essential for us. Many of us use it every day."
  • From Brazil: "I take part of a group that makes off-road rides along our desert beaches and the behaviour of the tides is essential to guarantee the safety of the ride."
  • From Florida: We used it this year during the opening days of lobster season to dive the Florida Keys Bridges at slack tide.  I owe you a lobster dinner!
  • From Australia: "I used it recently to plan a drilling investigation in Western Australia. A work schedule was planned to drill boreholes in the tidal zone.  Get in and get out - without getting wet!  I also used it to establish the approximate tidal range in the Philippines for a prospective project. My brother in Wales uses Tide Tool to time trips to the beach so his wife can ride her horse on the sands."
  • From Long Island Sound: "My hobby is metal detecting and I hit the beach a lot. I use it to find the real low tides by calculating the moon phase with the tide to get the lowest point possible. This way I find the good stuff."
  • From France: "My boat is used for scuba diving and fishing in Locquirec, Britanny. This little harbour has a tidal range of 9.90 m (32') and we have to deal with that: no water, only sand at low tide!"
  • From New York: "I have already used it to determine sunrise at Montauk Point Lighthouse for a photo session by my wife, and the tide a couple of miles along the beach to photograph gray seals."
  •   From Florida:  "Now when I leave the dock and have forgotten to check the tide on my PC in my rush to go, I don't have an anxiety attack."  (From a psychologist)
  • From Victoria, British Columbia: "As flatwater rowers on the Gorge/Selkirk Waterway, we rely a great deal on Tide Tool to help us anticipate the condition at the reversing narrows at Gorge-Tillicum Bridge. Only twenty feet wide at low tide and currents in excess of 11 knots at max, it's nice to know when not to go through. If you're just guessing, you might row up, but 20 minutes later you'll be stuck till next slack water (or swimming beside your upside-down shell!)."
  •   From California:  "I am a Supervisory National Park Ranger on Alcatraz Island.  Tide (and wind) affects our ability to get visitors on and off the island.  (Good thing the inmates didn't have Palms and your software!)"
    From Connecticut: "We are sea (ship) pilots in the Long Island Sound, Narragansett Bay, Cape Cod Canal, and points east. We probably have a hundred (or more) tide and current stations that we have to deal with. Until your program came along we had to lug a book of tide tables and currents around."
  • From Australia:  "I have found your program wonderfully helpful in my shipwreck conservation management program during field work and just want to thank you from the bottom of the ocean and the bottom of my heart."
  • From California: "I am a wildlife biologist and am very dependent on the tides here for my job. Now I have them in the palm of my hand. The days of the soggy tide book are over."
  • From Wales:  "I make regular wildfowl counts on estuaries and need to plan ahead when I can do them - the dates of the counts being dictated by the tides."
  • From Washington:  "A friend of mine is Muslim.  He asked me if I knew what time local sunset was, as he wished to end his fast for the day."
  •   From Maryland: "I live on Maryland's Eastern Shore. Last month I booked a charter on a Skipjack for a dozen friends to come to my dock. The Capt. said the charts showed there was not enough water. I whipped out my Palm and said there will be on September 12th at 7 p.m. (this was mid August). Astonished the Capt. said OK!?  But you still have to pay me if I can't get in. The tide was 2 feet above normal - just as it said!"
  • From New Zealand: "I use it in the film & TV industry for scheduling shooting days, it provides all the information we need to plan around sunrise/sunset and the tides."
  • From Maine: "That is sooo awesome. I am a guide for L. L. Bean. Several of us use your application."
  • From Washington: I've been using it to plan Puget Sound dives for our university scuba diving club.  I always have it with me (unlike paper tables) and I can look up the historic data for dives from a couple years ago when planning future dives.
  • From New Jersey: "Burlington City Fire Department & Endeavor Emergency Squad is responsible for river dive rescue and other emergencies so knowing the tidal change is very inportant.  We also use it for high tide stats to know when we can use the river for a water source by a Fire Engine."
  • From New Zealand: "I live on the south shore of the Waitemata Harbour (Auckland) and work on the north shore. Tide Tool lets me know when I can kayak to work (within 2 hrs of high tide) and when I'll end up walking most of the way through silt and mud!"
  • From Connecticut: We observe 'colors', the daily ritual of flag lowering, and like to be on time. The sun sets below our visible horizon and Tide Tool has been invaluable to settle all arguments. Once or twice a month we look for moonrise, jump in a boat and catch the moon rising out of Long Island Sound.
  • From Newfoundland: "As Commodore of a local yacht club we rely on tidal information to permit the launching, lift-out and servicing of many of our vessels. Now it's at our fingertips, any date any time."
  • From Morro Bay, California: "I walk my dogs at low tide. One of my dogs is a whippet and he needs a lot of space to run. I collect beach glass during the walks and the lower the tide the better."
  • From Hawaii: "I am a geologist, and much of our work is conducted in near shore areas. I find the Tide Tool is very helpful in predicting depths to shallow groundwater in tidally influenced areas when conducting subsurface investigations."
  • From New Jersey: "I plan my family vacation to the Jersey Shore using this tool. It's best during a week when low tide is in the afternoon. At low tide, the beach is wider and waves calmer, perfect for my two toddlers to play on the beach."
  • From South Carolina: "Here in Charleston, SC, the streets downtown often flood during high tide.  Tide Tool really helps me avoid traffic jams, or even worse, getting stuck!"
  • From Canada: "As the Rear Commodore for the Vancouver Branch of the Canadian Forces Sailing Association I have staffed the project to put your software on Palms into our over 25 foot vessels."
  • From Australia: I am a scuba instructor in Sydney and some of our dive sites are a little treacherous on certain tides and changes. Also some sites can only be dived at certain tides. It gives me a great indication of both the tide and the height of the tide. I know what sites I can use and what entry and exits I can use from the tide levels.
  • From California: "I'm the Navigator and Operations Officer on board a nuclear-powered fast-attack submarine home ported in San Diego. I have been using your Tide Tool from San Diego, CA to Esquimalt, B.C., to Ketchikan, Alaska, to Pearl Harbor, Hawaii, to Yokosuka, Sasebo, and Okinawa, Japan, to Chin Hae, South Korea, to Guam and back."  (Umm - great, but always check against reliable tide tables when safety of life or a billion dollar piece of the taxpayers' property is at stake. - WB)
  • From Long Island, New York: "We are water-skiers and we have a tournament-type slalom course set-up in a secret location. We have a small window at high tide when we can get our boats in there so we must follow the tides very closely."
  • From New Zealand: "I work with penguins around the southern coasts of New Zealand. Many colonies are only accessible at low tide."
  • From California: "I am a California Fish and Game Warden. I was recently given your email by the U.S. Coast Guard to obtain a tidal cycle application to put into my Palm Pilot."
  • From Georgia: "I am a Real Estate on Saint Simons Island, Georgia and I use Tide Tool to determine when I will take pictures of a property."
  • From Iceland: "I am a dentist in the U.S. Navy, stationed in Keflavík, Iceland. I am an avid surfer and fisherman and rely on tidal data to plan my recreational activities."
  • From California: "I use it for kitesurfing in the San Francisco Bay.  Best kitesurfing during ebb tide. I also hang glide on the cliffs.  If the winds die while we're flying, Tide Tool lets us know if there will be enough beach for a safe landing."
  • From South Carolina: I am the General Manager of a Planned Community on Hilton Head Island and will use the tide information to help set our work schedules. We are in the process of renovating several of our outfall structures that lead into tidal creeks.  We are also installing revetment along a bluff area. This will allow us to plan our work around low tide.
  • From New England: "I'm a U.S. Navy officer. Moving submarines into and out of drydock, we need to know which days will produce enough tide, and what time, so that docking evolutions can be scheduled, planned, and executed. The rapid currents often require certain craft movements be done at slack water. Even when we're not moving submarines around, there are few things as bothersome as walking out to inspect the pier and finding out that it's high tide when I get there." P.S.: When they dock a $1 billion nuclear submarine in shallow waters, they verify against the official NOAA tide tables.
  • From Norway: "Being in a long fjord; going from my harbour to the coastline takes me four hours against the tide and three hours if I go with the tide. Tide Tool helps me saving both time and fuel."
  • From California: As a professional photographer I'm doing portrait sessions at the beach every week and depend on Tide Tool to plan my sessions. 
  • From British Columbia: "I paddle Discovery Passage in my kayak. The currents run as hig as 15 knots with back eddies, whirl pools, and overfalls. I need to know the slack periods and the direction. If I'm wrong I won't get home that day. Not unusual to paddle 20 miles after work and before dark using the currents."
  • From Mississippi: "We use Tide Tool in planning hydrographic surveys in support of the US Navy. While we don't rely on your program as a data source for our collection of hydrographic data, we do use it to plan for tide ranges and the impact they will have on our operations worldwide."
  • From Washington: "I was working in the Duwamish Waterway with our E.P.A. dive team taking samples and placing cages with fish for a contaminant study.   I've loaded in Alaska, the West Coast of Canada, the US, Mexico and Pacific Islands (our Region supports work in American Samoa and other islands)."
  • From Florida: "We usually hunt fossilized sharks teeth which can only be done around low tide - now I can beat the neighbors for the good ones!"
  • From Maine: "Until recently, our office was located on the bank of the Kennebec River in Hallowell, Maine. The river is tidal, and frequently floods the parking lot at high tide, so Tide Tool helped me know when I needed to go down and move my car!"
  • From Thailand: "As a SCUBA instructor, I find it very handy to arrange my trips for my students' open water examinations."
  •   From New York: "I use it for planning paddle trips for a bird club, a paddling group, and for my agency, the NYS Dept. of Environmental Conservation."
  • From Brittany, France: "Since I'm a little boy, reading Tide Agenda in the newspaper is part of my life. Now, I can prepare fishing game (or picnics with family) for week-end, long time before, according to TideTool predictions. I beamed the software to a friend's Palm. In July, he went from Port-Navalo (Southern Britanny) to Jersey and Guernsey (Channel Islands). He just said 'This Tide Tool makes me crazy; You can't imagine how much time I spared using it, instead of usual calculation'. But yes, I just do imagine!"
  • From California: "I use it for planning coastal surveillance as a Navy Reservist."
  • From Sweden:  "In Europe at the North Sea shores one can walk out for kilometers (miles, whatever) as far as you can see at low tide. One needs to know when the water is supposed to come back, as you have absolutely no chance to survive (as numerous idiots prove every year) if you are out when the tide comes in."
  • From the southeast U.S.:  "I am an avid fly fisherman and here in the southeast our fishing success is greatly influenced by tidal conditions. My buddies that are using your program love it.  It helps them determine when to cut out of work for a few hours, when things are right!!!"
  • From England: "In Britain, a lot of rock climbing goes on on sea cliffs. Well, it is an island. Knowing the tide times becomes very important. I.e., are you going to be able to climb on a particular cliff at all? or will you go inland instead?"
  • From California: As a seabird surveyor for the Federal Government, I find your application indispensable when we need to use the boat for our surveys.  As a recreational birdwatcher, I use it frequently to see when it is best to head out to my favorite high-tide roost.
  • From Germany: "Your Tide Tool works great and is an absolute must in a city like Hamburg." (see postcard, right).  Andreas further advises: "The scene is real and happens every once in a while a 10 minute walk away from where I live. The guys from the fire department usually only watch it happening and only start retrieving cars which start to drift around. A big crowd is cheering for the owners who finally drop their trousers and try to get to their cars ..."
  • From Arizona:  "I teach an introductory oceanography class, and we take field trips to the Gulf [of Mexico] twice a year. For this, we have to pick times of the highest tidal range."
  • From Columbia: "We are having a great time using your tool to help knowing when we can navigate through the coral channels on the island of the Colombian Atlantic Coast."
  • From Florida:  "Hey Brother, you have a program that helps me catch the waves by letting me know when the tide is right for my local break.  Thanks from a Florida Surfer."
  • From New Zealand:  "G'day Walt - I live 10 minutes away from the world's most beautiful beach if it's low tide!  Otherwise, I live 10 minutes away from the world's rockiest beach."
  • From Puget Sound:  "I'm a sea kayaker, and have a PilotPro surgically implanted (according to my wife) -- one of the guys I work with has a Personal Pilot, and is a scuba enthusiast."
  • From California: "Tide Tool has already been really useful for planning beach and tidepool outings, making future camping reservations, etc."

Other Tide Software:

  • Tides lets you download, store and display tide tables on your Palm Pilot.  If you want to conserve RAM, or find Tide Tool too slow, and don't mind preloading the tables you need, you might prefer Tides.
  • XTide is a powerful Unix tide program, and the basis for Tide tool.  It has also been ported to Windows, OS/2, and the Mac.
  • What causes the tides? A fantastic explanation from the Dutch Directorate of Water Resources. Finally I understand why there is a high tide on the side away from the moon ...

Tide Tool was written by Walt Bilofsky.
Based on XTide, by Dave Flater, who also provides most of the tide data.
Fast Palm tide code by Jeff Dairiki.
French translation by Erick Beghin, Jean-Yves Pontailler, Jean-François Erismann, Philippe Nicolitch, François Meyniel, Michel Labelle and Rory Edwards.

After you've read the FAQ, you can email me at this link.