Is "unredactable" a word?

I googled it and even though it's been used on the Web, I can't find any entries for it on online dictionaries.

If it's not a real word, then is there a good equivalent?

The context is a record where new items can be added but existing items cannot be edited.

A good example would be the minutes of a meeting, where you can add new entries, but not change entries that have already been entered.

In cases where one wishes to negate a word whose "un" form is not standard, I prefer a hyphenated "non-" prefix, and would regard the usage as being the closest thing to a standard way of indicating the explicit opposite of a term. For example, an article about digital filters described the difference between linear and non-linear filters as being comparable to the difference between kangaroo biology and non-kangaroo biology. Even though the compound word "non-kangaroo" might never have been used anywhere previously, it clearly expresses its meaning, and a reader would be unlikely to worry about whether "non-kangaroo" was a "real word".

Additionally, in choosing between "non-redactable" and "unredactable", I would regard the former as clearly describing an inability to redact information, while the latter might be parsed as "unredact-able", meaning "able to unredact". The latter usage might make sense if one wanted a surveillance target to think he had destroyed information even though the information was, in fact, recoverable, but would not seem a good way to describe information which was conspicuously incapable of being redacted in the first place.

All that having been said, unless you are designing a versioning database which allows one to edit the "current" version of something but will maintain a journal of all edits, I think the term "append-only" might be more suitable.

try immutable

Not mutable; not capable or susceptible of change; not subject to mutation; unchangeable; invariable; unalterable.

of course, the word invariable as a synonym is also there :)

I would say "unalterable", but there's nothing wrong with "unredactable". If it has seen a noticeable amount of use, but isn't in the dictionaries, all that means is that the dictionaries haven't caught up with it yet.

A possible word for this would be "unexpurgatable." But I see nothing wrong with "unredactable." It would be a specialized use, obviously, for things that are normally subject to redaction.

Back when general fiction was subject to official censorship, special "unexpurgated" editions were occasionally available (e.g., the works of Henry Miller). So the word has general provenance.

It doesn't appear in the dictionaries and the Google Ngram Viewer gives 0% about its use; so no, it's not a word (or at least not a mentioned one in dictionaries... Although it fits the English morphology rules).

I'd propose "unmodifiable", if you want a single word.

I was thinking "uneditable" at first but it's used for next to nothing. "Unredactable" is basically never used.

See here: Uneditable is blue, unmodifiable is red, unredactable is green.