ISO 15919 Relation to other systems Comparison with UNRSGN and IAST

| Devanagari | ISO_15919 | UNRSGN | IAST | Comment_ |
|---|---|---|---|---|
| ओ /  ो | ō | o | o | To distinguish between long and short `o` in Dravidian languages, `o` now represents ऒ /  ॊ (short). Note that the use of ō is considered optional in ISO 15919, and using o for ओ (long) is acceptable for languages that do not distinguish long and short o. |
| ऋ /  ृ | r̥ | ṛ | ṛ | In ISO 15919, ṛ is used to represent ड़. |
| ॠ /  ॄ | r̥̄ | ṝ | ṝ | For consistency with r̥ |
| ऌ /  ॢ | l̥ | l̤ | ḷ | In ISO 15919, ḷ is used to represent ळ. |
| ॡ /  ॣ | l̥̄ | l̤̄ | ḹ | For consistency with l̥ |