The short version: Group Trip Cost works out what a group trip costs when everyone is starting from a different city. It is free, it runs entirely in your browser, and it is made by one person rather than a company.
Six people travelling from four cities cannot compare destinations with a single per-person figure. One party drives four hours; another buys three seats and a bag. A number that averages those two together describes nobody's trip.
Group Trip Cost bundles each candidate destination into one group total — every party's own flights or driving, the lodging for the whole group, shared costs and daily spend — and then ranks the destinations on cost against travel time. Each party's own share is always shown separately, because it is rarely equal, and the party carrying the longest journey is usually not the one paying the most.
Nothing in the destination library is invented. Every seeded figure carries the source it came from and the date it was recorded, and typing over one stamps it as yours instead.
Because the per-diem schedule is published month by month, the tool can show what a place costs in February against what it costs in July — which is often the largest single difference between two destinations, and the one people discover last.
It is not a booking site and it does not sell anything. There are no affiliate links, no commission on anything you book, and no paid placement: nothing in the rankings can be bought, and no destination is in the library because someone paid for it to be there.
The figures are planning estimates, not live fares and not quotes. They are meant to tell you which destination is worth pricing properly, not to replace pricing it properly. Confirm real prices with airlines, hosts and operators before committing money.
Group Trip Cost runs as a single page in your browser. There is no account, no sign-up, and no server holding your plan — party names, cities, prices and notes stay on your own device. A share link carries the plan inside the link itself rather than storing it anywhere. The privacy policy sets out exactly what a link does and does not expose.
An independent one-person project, not a company and not a team. The destination library is one person's research, recorded on a stated date and revised as better data arrives. That is also why corrections are genuinely useful rather than a formality — a real quote from a real trip is better evidence than anything a published average can offer.
Read by a person. Questions, bug reports, and corrections all go to the same place.
Correcting a figure. This is the most useful thing you can send. Say which destination, what you actually paid, for how many people and for which dates. Those go into the calibration the estimates are checked against, so a single real quote can improve what every later visitor sees.
There is also a feedback link on the main page, which attaches a short technical summary — how many parties and options you had, your screen size and browser version — to help reproduce a bug. It contains no destinations, prices or names, and you can delete any part of the message before sending.