Privacy Policy

What you enter

The calculators run in JavaScript on your own device. Salaries, birth dates, names, loan amounts — none of it is sent to a server, because for those tools there is no server to receive it. This site is a set of static HTML files.

Close the tab and it is gone. We do not store it, and for the calculators we have no mechanism to — there is no server for it to be stored on.

There are four exceptions. The first two are yours to trigger, and the data stays inside your browser. In the Bill Split Calculator you can save an event so you can reopen it later; doing so writes that event’s participant names, bill names and amounts to your own browser’s localStorage, and nothing is written unless you press save.

In the Expense Tracker, the transactions, categories and budgets you enter are written as you enter them — a ledger that forgets everything when you close the tab is not a ledger. There is no account and no server holding it for you, so the whole book lives in this one browser: the tool has an export button so you can back it up or move it to another device, and a button to erase it. Either way, nothing is sent anywhere.

The other two are a different kind, and data there genuinely does leave your device. Planning Poker is a tool several people share a room in. Nhà trọ is a rental noticeboard, published in Vietnamese only, where people post a room to let and strangers read it and call them — it is by some distance the largest collection of personal data on this site. Each has a section below.

When you use Planning Poker

Planning Poker is the one tool on this site where several people look at the same table, which makes it the one tool that sends what you enter to a server: the display name you choose, the room name, story titles and the card you play. There is no way for several people to share a table without the data passing through a server.

Everyone in the room sees your display name — that is what it is for. The card you play is different: while a round is still open, what the server sends each browser says only who has voted, never what they played.

A room lives on our server and expires four hours after it goes quiet; once it expires there is nothing left. No account, no email, no cookie. The display name is yours to choose — it can be anything — and it disappears with the room.

This tool alone writes one entry to your browser’s sessionStorage, under the key "poker:<room code>", so that reloading the page does not make you rejoin from scratch. It holds a participant id and a session token — not your name, not your votes — and sessionStorage clears itself when you close the tab. It is a different store from the localStorage list further down.

Your IP address is used to cap how many rooms one address can create, at twenty per hour, to stop rooms being created in bulk by a script. That counter lives for one hour and then deletes itself; it is not attached to a room or to your name.

When you send a report

The "Report a problem" button on every page is a different exception: what you write, the kind of problem, the page path, the tool and the language are sent to our server for handling — this data does leave your browser, unlike the calculations above.

Email is optional and used only to reply to you. If you leave one, it is stored with the report for up to 90 days and then deleted automatically; you can ask for earlier deletion at the contact address below. The server also records the request’s browser type (User-Agent), kept for the same 90 days, to tell a real report apart from automated bulk submissions. The IP address is used only briefly — up to one hour — to limit how many reports one address can send, and is not stored with the report itself.

If we enable an instant notification channel so we do not have to keep the admin page open, the full report — including the email you left, if any — is also forwarded there as soon as you submit.

When you post a rental listing

The rental noticeboard at /nha-tro is published in Vietnamese only, but what it collects is described here too, because it is the largest collection of personal data on this site and an English reader is entitled to know it exists.

Posting a listing sends what you fill in to our server and stores it: the title, the kind of property, the province and ward, the street address, the rent, the deposit, the floor area, the room counts, the description, the photos you upload, and the contact name and phone number.

The name and the photos are shown publicly to anyone who opens that listing, including people who never visit the rest of the site — a listing page is one search engines read. The phone number is shown masked (0901***567) in the feed and in the page source; the full number is returned only when a reader presses “show number”, and each IP address may do that a limited number of times per hour. That does not stop a determined person, but it does stop the board being scraped for numbers in bulk.

Before posting you must tick a box agreeing that the name and phone number you entered may be stored and shown publicly. We record that act alongside the listing: which version of the terms you were shown, and when you ticked it, by the server’s clock. That is the evidence the consent was given, and it is also what lets you ask us later what you agreed to. If the wording changes, the box comes back for everyone.

Posting needs no account, and that remains the default. If you choose to sign in with Google to keep your listings, the only thing our server stores is your Google account identifier — an opaque string — recorded against the listings you claim, so that changing device or clearing your browser does not lose them. Your email address travels in the sign-in token so the server can verify it, and is shown back to you in the page, but it is never written to our database. We also record separately, against that account identifier and for up to 400 days, that you accepted the posting terms, so you are not asked again every time.

Signing in happens directly between you and Google: we never see your password, while Google knows you used its account to sign in here and processes that on its own servers outside Vietnam under its own policy. Google’s library also writes session data into your browser under its own keys — those are not in the “toolist:” list below, because they are not ours. None of this happens if you do not sign in.

A listing is kept for at most 60 days and then deleted automatically, phone number and all. Refreshing a listing restarts that clock. You can delete it sooner with the management code you are given once when you post, which your browser keeps under “My listings” — or with your Google account, if you attached the listing to one. If you lose both, write to the contact address below with the listing URL and we will take it down.

If you paste a link into the “Facebook post” field, it is shown publicly on the listing page as a button. We accept only https links on facebook.com and read nothing from Facebook — the button is a link, not an embed, so opening a listing makes no request to Facebook.

Your IP address is used only briefly — up to one day — to cap how many listings one address can post and how often it can reveal a number, to stop bulk posting by a script. That counter is not stored with the listing and is not tied to your name.

We do not sell or share the name and number in your listing for marketing. But understand what posting publicly means: once a listing is up, anyone can read and copy by hand what is shown on it, and that is outside our control.

Syncing your settings (if you turn it on)

This is the only place on the site where something that otherwise lives only in your browser is sent to our server, and it is off by default. You can switch it on only after signing in with Google, with the “Đồng bộ cài đặt” checkbox in the navigation menu.

With it on, three things are stored on our server against your Google account identifier (uid): the tools you have starred, up to eight tools you opened most recently, and whether you chose the light or dark theme. Those three and nothing else. We do not store your email address in that record, nothing you enter into a tool, and no record of pages you viewed beyond that list of tools.

Weigh that middle item before switching it on: a list of recently opened tools says what you were working out. Somebody who opens severance pay, then insurance, then a loan schedule in one evening has said something about their week. That is why this is a separate switch, off by default, and not a consequence of signing in.

Lists are merged rather than overwritten: tools starred on this device and on another are added together, so turning syncing on never costs you a star. The record deletes itself 400 days after the last save.

Turning the switch off deletes the record from our server there and then, rather than merely stopping further writes. Signing out stops syncing but keeps the record, so it is there next time you sign in; to remove it outright, turn the switch off before you sign out, or write to the contact address below.

If you never turn it on, none of this section happens: those three values stay in your browser’s localStorage, exactly as they did before accounts existed.

Cookies and browser storage

The site sets no cookies of its own. It does use your browser’s localStorage to remember a few interface preferences: which tools you have starred, the handful you opened most recently, whether you chose the light or dark theme, and whether you have already seen the disclaimer notice and the quick guide.

Those hold tool identifiers such as “bmi”, a couple of true/false values and a version number — nothing you typed into a form. The other two — saved events from the Bill Split Calculator, and the Expense Tracker’s book — do hold what you typed.

All of them live on your device and are sent nowhere — not to us, not to a third party, not to your other devices. There is exactly one exception, and it happens only if you switch it on yourself: see “Syncing your settings” just below.

The first three in the list below — starred tools, recently opened tools, light or dark — are also the only three that sync if you turn it on. The expense book, saved bill-split events and rental management codes never do.

Clear them at any time by clearing site data in your browser; saved events and the whole expense book also have delete buttons inside the tools themselves. Clearing site data takes the expense book with it, so export it first if you still need it. If your browser blocks site storage, every tool still works; it simply will not remember your preferences or keep anything.

• toolist:favorites — the tools you have starred
• toolist:recents — up to 8 recently opened tools
• toolist:theme — light, dark, or follow the system
• toolist:bill-events — events you saved in the Bill Split Calculator: the event name, participant names, and each bill’s name and amount
• toolist:expense-book — the Expense Tracker’s book: each transaction (date, amount, category, note), the categories you named, your budget limits, and your recurring entries
• toolist:disclaimer-ack — which version of the disclaimer notice you accepted, so it is not shown again
• toolist:tour-seen — two true/false values: whether you have seen the quick guide on the home page and on a tool page
• toolist:rental-mine — the listing ids and management codes for rental listings posted from this browser, so the “My listings” page can reopen them; this is the only proof of ownership there is, and clearing site data loses it
• toolist:rental-saved — the ids of rental listings you bookmarked, to look at later; ids only, nothing about whoever posted them
• toolist:rental-compare — up to three listings you ticked to compare: id, slug and title, enough to reopen the comparison later; nothing about whoever posted them
• toolist:account-sync — one true/false value: whether you switched settings syncing on
• toolist:account-seen — one true/false value: whether this browser has ever signed in here, so the site knows whether it needs to load Google’s sign-in library at all

Third parties

Fonts are served from this domain rather than Google Fonts, so for most pages, rendering one makes no third-party request.

There are two exceptions, both images. The Vietnamese camera-rental page currently illustrates its equipment with product photographs served from Fujifilm’s own content network, so opening it makes your browser request them from that host, which sees your IP address and browser type. The other exception is rental listing photos, described below.

The site does load Google Analytics to measure traffic in aggregate: which pages are viewed, from where, on what kind of device. Google sets its own cookies for this and receives your IP address. Nothing you enter into a tool is sent to Google, and we do not use the service to identify anyone.

If you would rather not be measured, most content blockers and strict browser tracking-protection settings block this script, and every tool on the site keeps working without it.

Photos on rental listings are not hosted on this domain but on an external file-storage service. Opening a listing with photos makes your browser request them from that service, which sees your IP address and browser type, as it would for any image on the internet. When you upload a photo to post a listing, it goes straight from your device to that service rather than through our server.

The “Sign in with Google” button — in the rental section and in the navigation menu — calls Google’s authentication service, and only when you press it: Google’s library is downloaded at that moment rather than shipped on every page. The section “When you post a rental listing” above says what that records.

Pages in the rental section have one thing more: Google’s One Tap prompt may appear at the bottom of the screen when you are not signed in. On those pages — and only those — your browser fetches Google’s script as the page loads rather than waiting for a press, so Google receives your IP address and browser type at that point. Tool pages, the home page and the blog carry none of it.

The prompt never signs you in by itself: it always waits for you to choose an account, it can be dismissed, and if you dismiss it the site does not ask again for the rest of that browsing session. Ad blockers commonly block the script, and everything else in the rental section works the same when they do — the sign-in button in the menu is still there.

Server logs

The hosting provider keeps standard access logs — IP address, browser type and the path requested. That is the minimum required to serve a website, and we do not use it to identify anyone.

Most pages here are static HTML files served straight from a content delivery network, with no server running code in between. The rental pages are the exception: they are rendered on a server on every view, so that a listing’s content is in the page source for search engines to read. For those paths there is therefore one more server in the path of the request, keeping the same kind of technical log.