Require
XOR requires Windows 11 or Windows 10.
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Windows 11 | Windows 10 |
Usage
Reading two PDFs
When you launch XOR, the PDF selection window will be displayed.

After you select PDFs, if you move, rename or edit them, you need to reselect them.
After you select PDFs, if you move, rename or edit them, you need to reselect them.
When you select PDF, a thumbnail of the first page and file information are displayed.

Please press the [OK] button. A document window appears, and the two PDF files are displayed side by side. This is called the "Twin pages".

Comparison
Twin pages → Overlapped pages
Press the spacebar to switch to Overlapped pages. Overlapped pages is a composite of both PDF images. The red and blue areas are the differences. This is called the "Overlapped pages".

Overlapped pages → Blink pages
If you press the spacebar again, both PDFs will be displayed alternately. The difference appears to blink. This is called the "Twin pages".

Blink pages → Twin pages
Pressing the spacebar again will return to the "Twin pages".

Marking
You can mark the changes you have found with a square while these pages overlaped.
- Drag from top left to bottom right of the change
- Right click within the selection
- Select "Marking" from the context menu
Export/Print
You can export two paired PDF pages as a single PDF or print them out.
- Export:Ctrl + E
- Print:Ctrl + P

Subscription
The subscription agreement is necessary to use XOR. If you use XOR for the first time, there is a 1-month free trial period.
You may be hesitant to subscribe until you realize how beneficial the app is. So, subscribe and cancel your subscription immediately. You will be able to try the app for one month and your subscription will not be automatically renewed.
Subscribe & Tryal
Unsubscribe
FAQ
Price, Subscription, Purchase
How much is the price?
Subscription rate is ¥2,000(*) per month.
This contract is automatically renewed monthly, but you can cancel at anytime.
* Prices outside the Japanese store are determined by the exchange rate.
Is there a trial version?
If you use XOR for the first time, there is a 1-month free trial period.
You will need a Microsoft account to try it out.
What are the advantages of subscription?
- The initial cost is relatively low.
- You can cancel the contract when it is no longer needed. Therefore companies and organizations can control costs by increasing or decreasing team staff.
- There is no additional cost to upgrade to the new version of the app.
How do I sign up for a subscription?
You can subscribe in the app. Please refer to “Subscribe“ above.
How can I cancel my subscription?
You can unsubscribe in the app. Please refer to “Unsubscribe“ above.
How can I confirm the the expiration date of subscription?
Please refer to Expiration date to confirm the expiration date of subscription.
Can companies and organizations subscribe for the number of staff?
Yes.
Can I subscribe with an Ofiice365 account?
No. You need a Microsoft account to subscribe for XOR.
I think XOR is very expensive.…
XOR is an app for professionals who are not allowed to make trivial mistakes in production. Their number is limited. So we decided this price.
Moreover, we have many ideas of functions which could not be included in the current version of XOR due to priority reasons. We would be pleased if you understand that the price includes investment to realize them early.
Is there a packaged version?
No.
Can I purchase with a single payment?
No. It is only a subscription.
Can I purchase with a single payment?
No.
Can I purchase it outside the Microsoft Store?
No.
Fnction, Specification
Which OS will run XOR?
XOR requires Windows 10.
How much performance PC is required to use XOR?
It’s okay with an entry level PC. XOR is a very light app.
Can I compare grayscale PDFs?
Yes.
Can I compare RGB color PDFs?
Yes.
Can I compare CMYK color PDFs?
Yes.
Can I compare spot color PDFs?
No. It may be possible, but it is not guaranteed.
Can I compare other than PDF?
No. If you want to compare images please convert it to PDF.
When comparing with XOR, the text in the PDF is different from the display state of the original application.
The font data may not be embedded in the PDF. For example, if the application is Microsoft Word, please set up PDF export.
Can XOR notify me “how has it changed” not only “where”?
No.
For example, we can develop software logic to analyze and compare between old PDF and new PDF. It is effective if the order and number of all elements in both PDFs are the same. However, if some elements are moved or new things are inserted during the modification, the logic may report an incorrect comparison result because wrong element pairing will occur.
Also, even if the logic accurately reports “where has changed”, humans have to verify that it has been modified as intended. This circumstance will not be solved until the artificial intelligence technology catches up with humans.
Therefore, XOR only judges “where has changed”.
Are you planning to release the next version?
The current version of XOR does not have the features I want.
We hope so. We have lots of ideas of unrealized features.
However, the timing of the upgrade depends on the revenue of this app. That day may come sooner if you have recommended XOR to your colleagues or person who works in the same field.
Others
How should I call “XOR”?
Please pronounce it as | eks | oʊ | ɑːr |.
What is the origin of the name “XOR” ?
It is “eXclusive OR”. We expressed it as exclusive OR about how to find differences by overlapping pages.
What is FROGFISH?
Frogfish is the name of a very popular fish in scuba diving.
About 50 kinds of members of Frogfish have been found. Some species of frogfish can hunt other fishes using their own fishing rods and simulated bait.
Privacy
XOR is an offline application. It does not collect or transmit personal information or data other than subscription procedures.
Personal data when someone is inquired from this website will be used only for user support.
Terms of Use
Last updated: October 25, 2019
This document is the terms of use for the application “XOR for Windows” ( After this, it is written as “XOR” ) provided by FROGFISH.JP. Please read the following carefully before using XOR.
If you do not agree to some of the terms, you can not use this app. By using this app, you are agreeing to these terms.
Subscription
XOR is provided with the subscription agreement. The subscription rate is ¥2.000 or equivalent amount in local currency par a month. The contract will be renewed automatically every month unless you unsubscribe. The fee will be charged to your Microsoft account monthly.
You can use XOR until the expiration after unsubscribe. No cancellation of the current subscription is allowed during active subscription period.
Free trial
If you use XOR for the first time, there is a 1-month free trial period.
Free change
FROGFISH.JP may modify the subscription fees by sole discretion. The new fee will be applied after next update of the agreement.
Refund
Except when required by law, paid subscription fees are non-refundable.