Khmer Limon converter
Old Khmer documents opened — and put back again. Both directions, in your browser.
Why an old Khmer file opens as nonsense
Before Unicode there was no Khmer on a computer, only a Khmer font. Limon, ABC and the others put a Khmer glyph at each Latin code point, so a document was really the letters "sYs" with a font that drew them as Khmer. The text and the typeface were the same thing.
Open that file today without the exact font installed and you get the Latin back. The document is not corrupted and nothing is lost — it is simply a set of instructions to a font that is no longer there.
Why converting is not just swapping characters
A legacy file stores glyphs in the order they are drawn. Unicode stores them in the order they are read. The vowels េ ែ ៃ ោ and ៅ are drawn to the left of their consonant but belong after it, so every single one has to be moved across.
A converter that only substitutes character for character produces text that looks almost right and is wrong at every one of those vowels — wrong enough that search will not find it, a database will not match it, and a different font will draw it differently. This one moves them, and tells you how many it moved.
What it does not convert, and why that is deliberate
Subscripts were a separate set of glyphs at their own positions in the legacy font, with no coeng character involved at all — the stacking was the typeface’s doing. Those and a few rarer marks are left exactly as they arrived and listed underneath, rather than guessed at.
That is the important decision in this tool. Somebody converting a contract or a land title needs to be able to tell whether the job finished. An incomplete conversion you can see is safe; a complete-looking one that quietly invented characters is not, and the difference only shows up years later.
Both directions, and why the second one exists
Reading an old file is the common job. Writing Limon is the other one: a printer, a signwriter or a government office that still works in the old font and will not take Unicode. Press Swap and the tool turns round, taking the text with it.
That swap is also the quickest test of a conversion there is. Send the result back the other way, and if what comes out is what you started with, nothing was lost in between. The sample on the page does exactly that — it returns to the character it began as, which is how the awkward parts of the table were confirmed.
After you convert
Run the result through the Khmer Unicode checker on this site. Conversion is exactly the process that produces invisible ordering faults — characters in a sequence that renders correctly in one font and wrongly in another — and that checker is built to find them.
Then save it as Unicode and keep it that way. The whole point of the exercise is that the text stops depending on a font somebody has to install, and starts being readable by search engines, phones, screen readers and whatever comes next.