Using FastSeas by Satellite Email

Last updated: August 19, 2026

You can get routing and departure planning solutions from FastSeas via email (e.g. Iridium GO!, Sailmail, Winlink, and other email services) and via Garmin inReach and other short message satellite communicators such as Zoleo, Spot, and Bivy Stick devices. This is particularly useful when offshore or in remote anchorages, when you don't have access to high-speed internet. Results are provided by an automated email responder, which automatically calculates the route or departure planning result in response to your emailed request, and sends the result back to you in a reply email within a few seconds. Using the email responder service requires a FastSeas subscription.

Via Email (Iridium GO!, Sailmail, Winlink, etc.)

Routing Requests

To request a route using the email responder service, send an email like the one below:

To: query@fastseas.com
Subject: Bonaire-Porlamar
SEND ROUTE: 12.0N, 68.3W, 10.9N, 63.8W

Where 12.0N,68.3W are the coordinates of your departure point (in decimal degrees) and 10.9N,63.8W are the coordinates of your destination. The subject is not consequential - you can make it whatever you like. You can also specify coordinates in degrees and minutes if you prefer, as shown below:

To: query@fastseas.com
Subject: Bonaire-Porlamar
SEND ROUTE: 12-0N, 68-18W, 10-54N, 63-48W

Where 12-0N is 12 degrees 0 minutes North, and 68-18W is 68 degrees 18 minutes West.

A few minutes after sending your email, the automated email responder will send you a reply containing a GPX file which contains your routing solution. The GPX file contains waypoint data for your optimum route. Each waypoint contains predicted weather data for that waypoint in the waypoint description field. GPX files can be imported into a variety of chart plotters and navigation software (e.g. Navionics "Boating" app, OpenCPN, iNavX, Coastal Explorer, etc.). The GPX file is typically very small (less than 5 KB) and therefore very suitable for low bandwidth HF or satellite access.

The automated email responder will only respond to requests from authorized email addresses. That includes the email address you signed in with, or any email address you set up on the Account tab - where you can authorize your Iridium GO, SailMail, Winlink, and other email addresses.

If you prefer to get a Google Earth KMZ file instead of the standard GPX response, add a KMZ switch to your request as shown below:

To: query@fastseas.com
Subject: Bonaire-Porlamar
SEND ROUTE: 12.0N, 68.3W, 10.9N, 63.8W, KMZ

If you would like to receive a compressed GPX file (zipped), use a GPXZIP switch instead.

If you would like to limit the number of days included in the route mailed back to you, add a DAYS=3 switch, substituting the number of days you wish to receive:

To: query@fastseas.com
Subject: Bonaire-Porlamar
SEND ROUTE: 12.0N, 68.3W, 10.9N, 63.8W, GPXZIP, DAYS=2

You can also receive the routing data in a table (CSV file) using the CSV switch.

The default departure time for a routing request submitted via the email responder is "now." You can adjust the departure time using the optional DEPARTURE_DELAY_HOURS parameter. For example, use DEPARTURE_DELAY_HOURS=2 to set the departure time to two hours from now; or use DEPARTURE_DELAY_HOURS=24 to set the departure time to this time tomorrow (24 hours from now).

You can optionally include parameters to adjust your comfort criteria. To set the maximum wind you are willing to tolerate forward of the beam, use MAX_WIND_BEATING=20 (e.g. 20 kn). Use MAX_WIND_REACHING=30 to set the maximum wind you are willing to tolerate aft of the beam. Use MAX_WIND_GUST=50 to set the maximum wind gust you are willing to tolerate.

If you would like to disable ocean current effects in the routing calculation, add a NO_CURRENT switch to your request.

You can also optionally include parameters to adjust your polar performance and motoring criteria. To set the polar performance adjustment, use PERFORMANCE_ADJUSTMENT=90 (e.g. 90%). Use START_MOTORING=3 (e.g. 3 kn) to set the boat speed at which you will start motoring. Use MOTORING_SPEED=7 (e.g. 7 kn) to set the speed at which you motor.

Departure Planning Requests

You can also get departure planning results from FastSeas via email. To get departure planning results, send an email like the following:

To: query@fastseas.com
Subject: Bonaire-Porlamar
SEND DEPARTURE: 12.0N, 68.3W, 10.9N, 63.8W

The reply email will contain an attached table with your departure planning data.

Via Satellite Communicator (Garmin inReach, Zoleo, Spot, Bivy Stick, etc.)

The FastSeas email responder also supports Garmin inReach and other short message satellite communicators such as Zoleo, Spot, and Bivy Stick. Messages on these devices are generally limited to 160 characters of plain text, and so this imposes some limitations on what FastSeas can send.

Garmin inReach Routing Requests

InReach devices usually automatically provide your current location in messages sent from the device, so there's no need to provide your current/start position latitude and longitude when submitting routing and departure planning requests from your inReach device. If you wish to specify a departure position different from the one automatically reported by your inReach device, you certainly may include both departure and destination positions in your request.

When sending a request from an inReach device, you must include the EMAIL parameter, specifying the email address you signed in with (see the Account tab). This is required because messages from inReach devices don't provide a reply email address.

Example routing request:

To: query@fastseas.com
SEND ROUTE: 10.9N, 63.8W, EMAIL=YOUR_EMAIL@EXAMPLE.COM

Zoleo, Spot, or Bivy Stick Routing Requests

When sending a request from Zoleo, Spot, Bivy Stick, or another short message satellite communicator device, you must include the SHORT parameter, which tells FastSeas to respond using the short message format. You must also include both the start and destination latitude and longitude.

Example routing request:

To: query@fastseas.com
SEND ROUTE: 12.0N, 68.3W, 10.9N, 63.8W, SHORT

Some devices may require reply messages to be shorter than 160 characters. For example, Spot devices have a 140 character limit. You can configure a different maximum reply message length using the MSGLEN parameter, as shown in the example below:

To: query@fastseas.com
SEND ROUTE: 12.0N, 68.3W, 10.9N, 63.8W, SHORT, MSGLEN=140

Example Routing Request Response

Response messages are limited to 160 characters, so FastSeas will by default send a single compact reply message, consisting of the next 4 positions along the optimum route at 6 hour intervals. For example:

HOUR,LAT,LNG,WIND,COG
H0,11.58N,67.75W,15G18@78,126
H6,11.17N,67.16W,16G19@81,126
H12,11.04N,66.65W,10G14@110,59
H18,11.34N,66.02W,6G7@114,54,M

Where (looking at the first row of data):

If you need more waypoints, you can send a request with the optional WAYPOINTS and INTERVAL parameters, where WAYPOINTS determines how many waypoints will be sent (default is 4 waypoints), and INTERVAL determines how many hours between each waypoint (default is 6 hours). For example:

To: query@fastseas.com
SEND ROUTE: 10.9N, 63.8W, EMAIL=YOUR_EMAIL@EXAMPLE.COM, WAYPOINTS=24, INTERVAL=4

The example request above will send 24 waypoints with a 4 hour interval between each waypoint. If you request more data than can fit in a single 160 character message, FastSeas will reply with multiple messages. The example request above will result in a chain of 6 messages being sent in reply.

Departure Planning Requests

Departure planning responses to inReach and short message devices are similarly brief. The default response will include a single day (departing today) of departure planning stats sent in a single message. Example request:

To: query@fastseas.com
SEND DEPARTURE: 10.9N, 63.8W, EMAIL=YOUR_EMAIL@EXAMPLE.COM

Example response:

PLAN 1
DEP 16 APR 14:34Z
TIME 2d4h
MOTOR 0h
W-MIN 11
W-MAX-BEAT 19
W-MAX-REACH -
W-GUST 25
W-AVG 17
%BEAT 100
%CLS 0
%BEAM 0
%BRD 0
%RUN 0
BS-AVG 6.8

Where:

You can request several days of departure planning results by specifying the optional PLANS parameter in your request. The example request below requests 5 days of departure planning stats, which will result in 5 separate response messages being sent to your inReach device:

To: query@fastseas.com
SEND DEPARTURE: 10.9N, 63.8W, EMAIL=YOUR_EMAIL@EXAMPLE.COM, PLANS=5

Command Reference