Dutch spelling (spelling or spellingsregels) is standardised and periodically reformed by the Nederlandse Taalunie. The current standard is the 2015 Woordenlijst (with minor updates since). Key spelling rules: open and closed syllables determine single vs double vowels (leven vs lev-: double vowel only in closed syllables — been, boot, maan). Consonant doubling in closed syllables preserves the short vowel: man-nen, pet-ten, bit-ten. These rules explain most of Dutch spelling systematically.
The s/z and f/v spelling distinction: Dutch distinguishes between voiced (z, v) and voiceless (s, f) fricatives in spelling even when pronunciation neutralises them at word ends (final devoicing). Huis (house) ends in a voiceless s and was always voiceless — spelled correctly with s. Hond (dog) ends in a voiceless t-sound but is spelled with d — because in inflected forms (honden) the d is medial and voiced. This underlying-representation principle is the key to Dutch spelling logic.
Recent reforms addressed: compound words (are they written as one word, hyphenated, or separate? the 2005 reform simplified some cases), the words ending in -isch (elektrisch — already had the rule, but exceptions were clarified), the use of accents for disambiguation (een (a/an) vs één (one — with accent to avoid confusion)), and loanword spelling (many recent English loanwords are now given Dutch-adjusted spellings or kept as English — computer stays as computer, not kompjoeter). Always check Woordenlijst.org or Taaladvies.net when unsure — they are authoritative and free.