Performance analysis for offshore racing
Donkey Analytics reads the logs your instruments already keep and turns them into answers: how close you sailed to your polar, where each leg lost time, and whether the wind instruments can be trusted.
No card needed. The app runs in your browser at www.donkey.software.
A lap of the Isle of Wight, 14 Nov 2021, read from one Expedition log.Photo: the Needles
Reads the files your boat already makes
Boat Performance
Open a track and it's all there: sailing time, speeds and best VMG, percent of polar by wind speed and angle, tacks and gybes, shifts and gusts.
A real log, as the app shows it: the Solent, 14 November 2021, scored against the designer's polar.
What it answers
Boat performance
Score every minute of a log against your polar. See where the boat was quick, where it wasn't, and what each manoeuvre cost.
Race
Add the course and the race splits into legs, so you can see which ones cost you, and why.
Calibration BETA
Measure the boat's calibration from logs you already have: compass, heel and trim, boat speed, speed against heel, leeway and the wind. Each step is measured on data the earlier corrections have already been applied to.
Polars & targets
Build a polar from your own logs, tune it by hand and hold it against the designer's. Then take the targets back on board.
Also in the box
One subscription covers every tool, on every boat.
Compare against other boats' logs or a YB Tracking race file: places at every mark, wind lanes, the gap to the leader and a replay.
Personal bests and season-long trends across every log of a boat, including best VMG by wind band.
Plot any logged channel against another: timelines, scatter plots, histograms, heel and interval tables.
A printable debrief for each session, with coverage, polar %, manoeuvres, shifts and gusts. Save it as a PDF from your browser.
Draw where each sail flies by wind speed and angle, keep a chart for each boat, and export it as PDF or XML.
Trim a log to the race, join the days of a passage into one track, and export the result as GPX or CSV.
Drop marks on a chart or import them from GPX or CSV, then download the course as GPX.
A wind rose, hours by wind speed and angle, and sail use, from a qtVlm routing-statistics export.
Find GPS spikes, gaps and stuck sensors, and smooth noisy channels with a Kalman filter, without touching the original log.
How it works
Sign up at www.donkey.software with your email address and confirm it. You get 14 days with every feature, and no card is asked for.
Pick your boat's type from the list, then drop in logs from Expedition or Adrena, or GPX and KML tracks, several at a time.
Open a session, a race or a calibration run. Print the debrief and target cards, take the polar to Expedition, and go again.
Files
Bring the files your boat and your navigation software already write. Take the results back out in the formats they read.
| What | Brings in | Sends out |
|---|---|---|
| Logs and tracks | Expedition CSV logs, Adrena TRZ logs, GPX and KML tracks | GPX, CSV |
| Polars | Expedition and Adrena text polars; published ORC polars, by boat name or sail number | Expedition .pol |
| Courses | GPX, CSV | GPX |
| The fleet | Other boats' logs; YB Tracking race files (KML) | Stays in the app |
| Routing | qtVlm routing-statistics CSV | HTML report, PDF |
| Calibration | Your logs | PDF report, NKE-style correction tables |
| Sail crossovers | Its own XML | XML, PDF |
| Your library | Built as you go | One zip: every track as CSV and GPX, polars as .pol, plus boats, courses and races |
Not yet: NMEA 0183, NMEA 2000 and B&G log files. They're on the roadmap. If that's what your boat records, tell us.
Pricing
Every feature is included. What you pay depends on how many boats you analyse, and what they are.
Donkey Analytics
From£40per boat
per month
14 days free. No card needed.
Billed monthly in pounds sterling through Stripe.
Your data
Your tracks are your crew's work. They live in a private library, you can take them with you whenever you like, and they are never sold.
Every account has its own library. We don't sell your data, show it to other users or use it for advertising.
One download holds your whole library: tracks as CSV and GPX, polars as Expedition files, plus boats, courses and races. It still works after a trial or subscription ends.
Ask us to close your account and we delete it, usually within a few days, and cancel any subscription with it.
Card details go straight to Stripe and never reach our server.
One cookie keeps you signed in to the app. There are no advertising or analytics cookies, there or here.
Protect your account with an authenticator app, with single-use recovery codes in case you lose your phone.
When an account is deleted we keep an anonymised copy of its tracks, with no names, dates or boat, to improve the analysis. The privacy notice has the details.
About
Donkey Analytics started as a set of scripts written between races, to answer the questions the crew kept asking: were we on polar, was the wind instrument lying, which sail should have been up? It has grown into a full toolkit for boats that race offshore, still shaped by what helps on the water.
Why a donkey? Because it carries the load, doesn't complain, and looks you straight in the eye.
Donkey Analytics is independent. It is not affiliated with, or endorsed by, the Royal Ocean Racing Club (RORC) or the IRC Rating Office.
No. Donkey Analytics runs in a modern web browser and is designed for a laptop or desktop screen. Sign up or sign in at www.donkey.software.
Instrument logs from Expedition (CSV) and Adrena (TRZ), and GPX or KML tracks from chartplotters, trackers and phone apps. Polars from Expedition or Adrena text files, or a published ORC polar. Courses as GPX or CSV, YB Tracking race files for the fleet, and qtVlm routing statistics.
NMEA and B&G log files aren't supported yet. The formats table has the full list.
It needs an internet connection, because it runs on our server. Do the analysis ashore, then take printed target cards and debriefs to sea. It's for looking back at your sailing: never use it for navigation or safety.
Not today. Donkey Analytics looks at what the boat did. It doesn't work out handicap results, route the boat or show forecasts.
Sign up with your email address and confirm it. Your 14 days start when you create the account. No card is needed, and nothing is charged when the trial ends.
After the trial the app is locked until you subscribe, but your library stays, and you can still download all of it.
Each boat is billed monthly at the price for its type, from £40 to £120 a month. You pick the type from a list when you add the boat, and you see its price, and your monthly total, before you agree to anything.
Yes, at any time. The billing page opens Stripe's customer portal, or you can email us. The subscription then runs to the end of the month you've paid for.
If you're buying as a consumer, you can also cancel within 14 days of subscribing and get back what you paid, less the time you used. The terms have the details.
Not yet. An account is for one person. Shared access for a crew is on our roadmap.
You. Your library is private to your account, and we don't sell your data or show it to other users. The people who run the service can see your account details and the names and sizes of your tracks, and open a track only if you ask them to.
This website, donkeyanalytics.co.uk, tells you about Donkey Analytics. The app itself runs at www.donkey.software, and our email comes from addresses ending @donkeyanalytics.co.uk.
Those are the only addresses we use. If something claiming to be from us comes from anywhere else, don't trust it.
No. Donkey Analytics is independent. It is not affiliated with, or endorsed by, the Royal Ocean Racing Club or the IRC Rating Office.
Load a track from your last race and see where the time went. Free for 14 days, and no card needed.
You'll sign up at www.donkey.software, the Donkey Analytics app.
