ACI File

What are ACI files and how to open them

Are you having problems opening an ACI file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your ACI files.

What is an ACI file?

An .ACI file is an ACI Development Appraisal Data file.

ACI Development Appraisal Data files are proprietary report data files created by ACI Software's appraisal software suite, used primarily for drafting, storing, and exchanging real estate appraisal reports. These files store complete appraisal data including property details, borrower and client information, finance, inspection notes, sales comparables, legal descriptions, and all other elements used during the appraisal process. They are not image or PDF files but structured data intended to be processed by ACI's software.

Such files are written by the ACI Report program (part of ACI Software's product line) when saving or exporting an appraisal in ACI's internal report format. Users work in this software to fill in forms, capture inspection details, input sales data, and when saved, all that information is serialized into the .ACI format. They are typically read back only by the same ACI product when loading reports, editing them further, or submitting them for review or delivery to portals that accept ACI files.

Internally, .ACI files contain ASCII-identifiable strings like PROPERTY, ADDRESS, BORROWER, CLIE­NT, COM­MENTS, INSPECT, SPECIAL, AMOUNT, PRICE, TRANS, CITY, DATE, NAME, etc., along with header signatures: at offset zero, bytes 52 41 50 49 44 21 65 00 ("RAPID!e"), and at offset 1024, bytes 52 6F 6F 74 20 45 6E 74 72 79 ("RootEntry"). These markers plus the embedded field names allow detection of the format via file-signatures.

How to open ACI files

Important: Different programs may use files with the ACI file extension for different purposes, so unless you are sure which format your ACI file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested ten different ACI openers which you will find listed below.

Last updated: August 16, 2026

Various apps that use files with this extension

These apps are known to open certain types of ACI files. Remember, different programs may use ACI files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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File.org helps thousands of users every day, and we would love to hear from you if you have additional information about ACI file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.