Be advised that the "service" offered at the URL specified violates most font licenses in either one or two ways.
(1) Many font licenses specifically prohibit conversions of any form such as from TrueType to Type 1, Type 1 to TrueType, whatever to OTF, TTC to component TTF, etc.
(2) This online converter requires uploading a file to a third party. Virtually no font licences allow such transfers of fonts to third parties unless the third party has their own license for the font(s) in question.
Also note that the online "service" pointed to also claims to support extraction of fonts from PDF files. Note that such extraction and use is not only against most font licenses, but also yields incomplete and effectively useless font files. The font data embedded in a PDF file (or for that matter in EPS or PostScript) is not the full font file. Obviously an embedded subset has the problem of missing glyphs and most fonts embedded in PDF (or EPS or PostScript) files are small subsets of the fonts' original complement of glyphs. But in addition, a significant amount of font metric information association with pair kerning, bounding boxes, etc. is not embedded and therefore is missing in any extraction.