| 497 | A Guide To Reading and Writing Japanese (Florence Sakade) |
| 597 | A Guide To Reading and Writing Japanese 3rd edition (Henshall, Seeley and De Groot) |
| 568 | A Guide To Remembering Japanese Characters (Kenneth G. Henshall) |
| 292 | A New Dictionary of Kanji Usage |
| 129 | Classic Nelson (Andrew Nelson) |
| 281 | Essential Kanji (P.G. O’Neill) |
| 526 | Japanese Kanji Flashcards (Max Hodges and Tomoko Okazaki) |
| 120 | Japanese Names (P.G. O’Neill) |
| 3.16 | Japanese for Busy People |
| 520 | Kanji and Kana (Spahn and Hadamitzky) |
| 529 | Kanji and Kana, 2nd Edition (Spahn and Hadamitzky) |
| 423 | Kanji in Context (Nishiguchi and Kono) |
| 767 | Kodansha Compact Kanji Guide |
| 15 | Kodansha Kanji Dictionary (Jack Halpern) |
| 6 | Kodansha Kanji Learner’s Dictionary (Jack Halpern) |
| 6 | Kodansha Kanji Learner’s Dictionary, 2nd Edition (Jack Halpern) |
| 642 | Les Kanjis dans la tete (Yves Maniette) |
| 10299 | Morohashi |
| 15 | New Japanese English Character Dictionary (Jack Halpern) |
| 1781 | New Nelson (John Haig) |
| 635 | Remembering The Kanji (James Heisig) |
| 685 | Remembering The Kanji, 6th edition (James Heisig) |
| 188 | The Kanji Way to Japanese Language Power (Dale Crowley) |
| 453 | Tuttle Kanji Cards (Alexander Kask) |
Jōyō kanji, taught in grade 4
JLPT level N3
265 of 2500 most used kanji in newspapers
Stroke order
On reading compounds
- 必 【ヒツ】 definiteness, certainty
- 必需 【ヒツジュ】 necessary
Kun reading compounds
- 必ず 【かならず】 always, without exception, necessarily, certainly, without fail, positively, invariably
- 必ずしも 【かならずしも】 (not) always, (not) necessarily, (not) entirely, (not) all
Readings
- Korean:
- pil
Spanish
- sin falta
- necesariamente
- inevitable
- ciertamente
Portuguese
- invariavelmente
- inevitável
- certo
French
- nécessairement
- certain
- inévitable
- invariablement
| 359 | 2001 Kanji |
| 0a5.16 | The Kanji Dictionary |
| 1-1-4 | SKIP code |
| 4-5-4 | SKIP code |
| 3300.0 | Four corner code |
| 1-41-12 | JIS X 0208-1997 kuten code |
| 5fc5 | Unicode hex code |
Jōyō kanji, taught in grade 4
JLPT level N3
106 of 2500 most used kanji in newspapers
Stroke order
On reading compounds
- 要 【ヨウ】 main point, essential point, important thing, necessity, need, requirement
- 要因 【ヨウイン】 main cause, primary factor
- 所要 【ショヨウ】 required, needed, necessary
- 法要 【ホウヨウ】 Buddhist memorial service
Kun reading compounds
- 要る 【いる】 to be needed, to be necessary, to be required, to be wanted, to need, to want
- 要 【かなめ】 pivot, vital point, cornerstone, keystone, Japanese photinia
- 要石 【かなめいし】 keystone
Readings
- Japanese names:
- とし
- Korean:
- yo
Spanish
- necesidad
- punto central
- esencia
- necesitar
Portuguese
- necessidade
- ponto principal
- essência
- pivô
- chave para
French
- besoin
- point principal
- pivot
- essentiel
- point clef
| 729 | A Guide To Reading and Writing Japanese (Florence Sakade) |
| 623 | A Guide To Reading and Writing Japanese 3rd edition (Henshall, Seeley and De Groot) |
| 593 | A Guide To Remembering Japanese Characters (Kenneth G. Henshall) |
| 117 | A New Dictionary of Kanji Usage |
| 4274 | Classic Nelson (Andrew Nelson) |
| 262 | Essential Kanji (P.G. O’Neill) |
| 887 | Japanese Kanji Flashcards (Max Hodges and Tomoko Okazaki) |
| 1218 | Japanese Names (P.G. O’Neill) |
| 3.16 | Japanese for Busy People |
| 419 | Kanji and Kana (Spahn and Hadamitzky) |
| 425 | Kanji and Kana, 2nd Edition (Spahn and Hadamitzky) |
| 424 | Kanji in Context (Nishiguchi and Kono) |
| 1639 | Kodansha Compact Kanji Guide |
| 3263 | Kodansha Kanji Dictionary (Jack Halpern) |
| 1683 | Kodansha Kanji Learner’s Dictionary (Jack Halpern) |
| 2290 | Kodansha Kanji Learner’s Dictionary, 2nd Edition (Jack Halpern) |
| 1618 | Les Kanjis dans la tete (Yves Maniette) |
| 34768P | Morohashi |
| 2635 | New Japanese English Character Dictionary (Jack Halpern) |
| 5515 | New Nelson (John Haig) |
| 1604 | Remembering The Kanji (James Heisig) |
| 1730 | Remembering The Kanji, 6th edition (James Heisig) |
| 78 | The Kanji Way to Japanese Language Power (Dale Crowley) |
| 536 | Tuttle Kanji Cards (Alexander Kask) |
| 3269 | 2001 Kanji |
| 3e6.11 | The Kanji Dictionary |
| 2-6-3 | SKIP code |
| 1040.4 | Four corner code |
| 1-45-55 | JIS X 0208-1997 kuten code |
| 8981 | Unicode hex code |