Privacy Policy
Effective date: September 30, 2026
Visit statistics
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Fillus (필어스) (“we”) runs this collection of web tools (“this site”). We publish this Privacy Policy under Article 30 of the Personal Information Protection Act of the Republic of Korea.
This site has no sign-up and no input forms. We receive personal information in only three ways: emails you send us, visit statistics, and access logs. This policy covers the whole site, including its Korean pages.
1. Why we process personal information
- Emails: to answer your questions and bug reports, and to fix the bugs you report.
- Visit statistics: to count how much each tool is used, so that we can improve the site.
- Access logs: to run the site securely and to detect outages and attacks.
We do not use personal information for any other purpose. If a purpose changes, we will update this policy first.
2. Personal information we process
| Type | Items | How we receive it |
|---|---|---|
| Emails | Your email address, your name (if you include it), the message and any attachments, and the time it was sent | Emails you send to our contact address |
| Visit statistics | The kind of page viewed, whether you saw a tool’s result, whether the visit is a first or a return visit, the referring page (the address of the previous page), screen size, browser language, estimated browser, operating system, device type, country, region, and city (estimated from your IP address; we do not store your IP address) | Automatically when you open a page |
| Access logs | IP address, time of access, the address of the requested page, browser information, and the referring page (the address of the previous page) | Automatically by our server when you open a page |
Visit statistics do not store your IP address and do not collect information that identifies you. What you enter into a tool, and its results, are not sent in visit statistics.
3. How long we keep it and how we delete it
| Type | How long we keep it |
|---|---|
| Emails | 1 year from the day we finish replying |
| Visit statistics | 13 months from the day they are collected |
| Access logs | 2 years from the day they are recorded |
When the period ends, we delete the information without delay. We delete emails from the mailbox, and we delete visit statistics and access logs from storage so that they cannot be restored. After deletion, visit statistics remain in our company backup copies for up to 1 more year and are then deleted. Records that a law requires us to keep longer are kept separately for that period.
4. Sharing with third parties
We do not provide personal information to third parties, except where a law requires us to.
5. Browser storage
We do not set cookies ourselves. To make the tools easier to use, we keep the values below in your browser’s storage (localStorage). These values stay in your browser and are not sent to us.
| Value stored | What it is used for | How to delete it |
|---|---|---|
| The values you last entered in a calculator | The calculators on the Korean pages: VAT, loan interest, date, D-day, savings, pyeong (floor area), percentage, and severance pay | The calculator’s button for deleting saved values, or deleting this site’s data in your browser settings |
| A D-day list (names and dates) | The D-day calculator on the Korean pages | Removing items from the D-day list, or deleting this site’s data in your browser settings |
| First-visit marker | One marker that tells visit statistics whether a visit is a first or a return visit. It holds the date of your first visit and is used for 13 months | Deleting this site’s data in your browser settings |
| Visit statistics opt-out marker | One marker that keeps visits from this browser out of visit statistics | The “Opt back in to visit statistics” button, or deleting this site’s data in your browser settings |
The first-visit marker never leaves your browser. The only thing sent in visit statistics is whether the visit is a “first visit” or a “return visit”. The marker holds the date of your first visit. Once 13 months have passed since that date, the marker is treated as absent and your next visit is counted as a first visit again. Return visits do not update the date. Markers set before this 13-month lifetime was introduced have no date, so the first time you open a page after that, the marker is given that day’s date. If you delete the marker, your next visit is counted as a first visit.
To opt out of visit statistics, press the “Opt out of visit statistics” button on this page. This deletes the first-visit marker, and from then on this browser keeps no first-visit marker and sends no visit statistics. To remember your choice, we keep one marker in your browser’s storage. If you delete this site’s data in your browser settings, this marker is deleted too, and your visits are counted again. You can still use every tool after opting out.
What you enter into a tool is processed only in your browser. It is not sent to our server, to advertisers, or in visit statistics requests.
6. Share links
A share link for a calculator result contains the values you entered (including D-day names). Anyone who receives the link can see all of those values. If you entered information such as another person’s name, please check before you send the link.
The values in a share link come after the “#” in the address, so they are not sent to the server, and they are removed from the address as soon as the page opens.
7. Outsourcing and international transfer
When we reply to your email, we have the provider below send the reply for us. Sending is handled on servers in Seoul, Republic of Korea, and your personal information is not transferred outside Korea.
| Provider | What we entrust to it |
|---|---|
| Amazon Web Services Korea LLC | Sending replies to your emails (Amazon SES) |
This site, visit statistics, and the receiving and storing of emails are handled on servers that we run ourselves in Korea.
8. Advertising and third-party cookies
This site shows ads through Google AdSense. There are no ads on the About, Contact, and Privacy Policy pages.
Third party vendors, including Google, use cookies to serve ads based on a user’s prior visits to this website or other websites. Google’s use of advertising cookies enables it and its partners to serve ads to users based on their visit to this site and/or other sites on the Internet. Some of these cookies are stored under this site’s address.
| Item | Details |
|---|---|
| Collection technologies | Cookies, web beacons, device identifiers, and other ad technologies |
| Type | Third-party cookies |
| Who collects | Google LLC and third-party ad vendors certified by Google |
| What is collected | Visits to this site and to other websites, ads viewed or clicked, IP address, and browser and device information |
| Purpose | To serve ads and measure their performance, and to choose ads that match your interests |
| How to opt out | The three ways below |
There are three ways to opt out of personalized ads.
- Users may opt out of personalized advertising by visiting Ads Settings.
- Users may also opt out of a third-party vendor’s use of cookies for personalized advertising by visiting www.aboutads.info.
- You can block or delete cookies in your browser settings.
If you turn off personalized ads or block cookies, you will still see ads, but they will not be based on your interests. To learn how Google uses information from sites that use its services, see Google’s explanation.
Google and other third-party ad vendors may collect information about your online activities over time and across different websites, including this site, when you use this site. Ad cookies go directly from your browser to Google and other ad vendors, and we do not receive that information.
Do Not Track. We do not change how this site collects information in response to “Do Not Track” signals from your browser. Instead, you can opt out of our visit statistics with the button on this page (section 5), and opt out of personalized ads in the ways above.
US state privacy laws. When this site shows ads to visitors in US states that have consumer privacy laws, it also shows a Google message with a link to opt out of the sale or sharing of your personal information for targeted advertising. If you opt out, Google shows you only non-personalized ads on this site. In those states, Google also treats a Global Privacy Control signal from your browser as the same request.
9. Your rights and how to use them
You can ask us to let you see your personal information, or to correct it, delete it, or stop processing it. Send your request to the email address below, and we will respond within the period required by law. You can also make a request through a representative. You can use these rights wherever you live.
- Email: toolbox@gofillus.com
Visit statistics and access logs are not linked to names or email addresses, so we may not be able to find the records that belong to you. In that case, we will tell you why.
10. Security measures
- Only the people who run the site can see the email inbox, visit statistics, and access logs.
- The admin screen and storage for visit statistics are not open to the internet.
- Records whose period has ended are deleted as described in section 3.
11. Privacy officer
| Item | Details |
|---|---|
| Name | Kiwan Park (박기완) |
| Position | Representative |
| Contact | toolbox@gofillus.com |
Please send questions, complaints, and requests for remedies about personal information to the contact above.
12. Remedies for privacy violations
If you need a remedy or advice about damage from a privacy violation, you can contact the Korean agencies below.
- Personal Information Dispute Mediation Committee: www.kopico.go.kr, phone 1833-6972
- Personal Information Infringement Report Center (Korea Internet & Security Agency): privacy.kisa.or.kr, phone 118
13. Changes to this policy
This policy applies from the effective date above. When it changes, we post the new policy on this page and record the effective date and the changes in the table below.
| Effective date | Changes |
|---|---|
| September 29, 2026 | First version |
| September 30, 2026 | Added how to opt out of visit statistics to section 5 |
| September 30, 2026 | Added the 13-month lifetime of the first-visit marker to section 5, and published this policy in English |