Planets Word Search
Free printable planets word search puzzles: explore the Solar System through planets, moons and space vocabulary, from a beginner grid to real astrophysics.
This Planets collection includes three word searches built around our solar system, each aimed at a different kind of solver. Easy covers the planets nearly every child already knows in order. Medium adds real astronomical vocabulary. Hard turns to the precise vocabulary of planetary science. The wider universe beyond our own solar system is covered in our Space collection.
Every printable PDF includes an answer key and is reviewed before publication.
Planets — Easy Word Search
| Grid size | 12x10 |
|---|---|
| Words to find | 10 |
| Font size | 16 pt |
| Paper | A4 & US Letter |
| Answer key | Included (page 2) |
| Puzzle ID | P-E-029 · v2026.4 |
Best for ages 5–8 and first-time solvers.
This is for a young solver who already knows the planets in order, and just wants to find them in the grid.
Words run only left-to-right or top-to-bottom, so there's no hidden trick waiting for a beginner.
It's the version for a first science lesson, an early classroom activity, or a calm few minutes with a pencil.
Vocabulary analysis
Measured directly from this puzzle's own grid — not a generic estimate.
With an average word length of 5.4 letters, this puzzle sits at a moderate 45.0% grid coverage, balancing genuine challenge with enough empty space to keep scanning manageable. 1 of its words share letters with at least one other word on the list, so a single letter in the grid can belong to more than one hidden answer — a real source of extra difficulty beyond word count alone.
Why we chose this word list
We kept Pluto out on purpose: since its 2006 reclassification as a dwarf planet, we teach the eight-planet model accurately rather than the nine most solvers grew up with.
Every planet name here is also its own memorable word, so this puzzle doubles as an order-of-the-planets memory exercise.
Why this level is easy
- Only horizontal and vertical words — no diagonals
- No reversed words
- Short, everyday vocabulary
- No uncommon spellings
- Minimal overlaps between words
Planets — Medium Word Search
| Grid size | 15x15 |
|---|---|
| Words to find | 15 |
| Font size | 13 pt |
| Paper | A4 & US Letter |
| Answer key | Included (page 2) |
| Puzzle ID | P-M-029 · v2026.4 |
Ideal for upper elementary students and casual puzzle fans.
This version moves past the planet names into real astronomical vocabulary, the words that describe how the solar system actually works.
Diagonal words appear here for the first time, so scanning takes real attention rather than a straight read.
It sits between a beginner's puzzle and a real challenge, without needing an astronomy degree to solve.
Vocabulary analysis
Measured directly from this puzzle's own grid — not a generic estimate.
With an average word length of 6.9 letters, this puzzle sits at a moderate 45.8% grid coverage, balancing genuine challenge with enough empty space to keep scanning manageable. 5 of its words share letters with at least one other word on the list, so a single letter in the grid can belong to more than one hidden answer — a real source of extra difficulty beyond word count alone.
Why we chose this word list
We distinguished "asteroid", "meteor" and "comet" deliberately — three genuinely different objects often used interchangeably, which this puzzle treats correctly.
"Axis" and "rotation" are paired because a planet's tilt on its axis, not just its rotation, is what actually causes seasons — a common misconception worth correcting.
Why this level is medium
- Horizontal, vertical and diagonal words
- No reversed words
- Mixed word lengths, some less common vocabulary
- Moderate overlaps between words
Planets — Hard Word Search
| Grid size | 20x20 |
|---|---|
| Words to find | 20 |
| Font size | 11 pt |
| Paper | A4 & US Letter |
| Answer key | Included (page 2) |
| Puzzle ID | P-H-029 · v2026.4 |
Designed for experienced solvers and adults.
This is for someone who wants the precise vocabulary of planetary science, not just a longer list of planet names.
Every direction is in play, including reversed words, with filler letters built to resemble genuine answers.
It takes sustained attention rather than a glance, built for someone who takes astronomy seriously.
Vocabulary analysis
Measured directly from this puzzle's own grid — not a generic estimate.
With an average word length of 10.5 letters, this puzzle sits at a moderate 52.5% grid coverage, balancing genuine challenge with enough empty space to keep scanning manageable. 7 of its words share letters with at least one other word on the list, so a single letter in the grid can belong to more than one hidden answer — a real source of extra difficulty beyond word count alone.
Why we chose this word list
"Perihelion" and "aphelion" are the precise terms for a planet's closest and farthest points from the Sun — exact vocabulary, not simplified synonyms for "near" and "far".
"Exoplanet" and "habitable" are included together since the search for potentially habitable exoplanets is one of the most active areas of current astronomy research.
Why this level is hard
- All eight directions, including reversed words
- Longer, denser word list
- Similar-looking decoy letter sequences in the filler
- Frequent overlaps between words
Planets — Large Print Word Search
Designed specifically for adults, seniors and anyone who prefers easy-to-read puzzles.
| Grid size | 15x12 |
|---|---|
| Words to find | 15 |
| Font size | 22 pt |
| Paper | A4 & US Letter |
| Answer key | Included (page 2) |
| Puzzle ID | P-L-029 · v2026.1 |
Best for adults, seniors, and anyone who prefers larger, easier-to-read print.
Vocabulary analysis
Measured directly from this puzzle's own grid — not a generic estimate.
With an average word length of 6.9 letters, this puzzle is densely packed at 57.2% grid coverage — less empty space means fewer easy gaps to scan past, so finding each word takes closer attention.
Why this is a Large Print edition
- All eight directions, including reversed words — same rule as Hard
- Same word list and word count as our Medium puzzle — full challenge, not a simplified one
- 15×12 grid: fewer rows than a standard 15×15, freeing real vertical space for larger lettering
- 20pt or larger lettering throughout, verified to actually fit the grid, not just requested
- Simplified Puzzle Passport with no fill-in blanks, leaving maximum room for the letters themselves
Editorial review
Every puzzle is reviewed by our editor, Ferran Sarrió, after automatic generation. We verify vocabulary, placement rules, answer key accuracy and print quality before publication, according to the Modern Word Search methodology.
- Vocabulary checked
- Difficulty verified
- Solution verified
- Print layout verified
Reviewed by · August 2026. First published August 2026. Next scheduled review: Winter 2027.
More science word searches
6 of 24 science word searches puzzles shown below, each following the same published specification.