LinkedIn Mini Sudoku #161 (Nineteen) - January 19, 2026: Step-by-Step Solution Guide

Crack today's LinkedIn Mini Sudoku #161 (Nineteen), a tricky 6x6 number puzzle published on January 19, 2026. This daily brain teaser requires filling the grid so each row, column, and 2x3 section contains digits 1-6 exactly once. We'll walk through the logical steps to solve it from the given clues, focusing on naked singles, process of elimination, and box completions. Let's dive in!

Here's the starting grid for reference (prefilled clues marked):

  1 2 3 4 5 6
1 . 2 . . . .
2 1 3 . 2 4 6
3 . 4 . 6 . 5
4 . 5 . 3 2 4
5 . 6 . . . 2
6 . . . . . 3

Step 1: Analyze Rows with Most Clues - Fill Row 2 Completely

Row 2 already has 1, 3, 2, 4, 6. The only missing number is 5, which must go in column 3 (the empty cell). Place 5 there.

Row 2 now: 1 3 5 2 4 6

This immediately helps column 3 and the top-right 2x3 box.

Step 2: Top-Left Box - Naked Singles Emerge

The top-left 2x3 box (rows 1-2, columns 1-3) now has 1 (r2c1), 2 (r1c2), 3 (r2c2), 5 (r2c3). Missing: 4 and 6.

• Column 1 can't have 1 (r2), so r1c1 possibilities narrow.
• Look at row 1: has 2 in c2. Column 1 sees 1 (r2), 5? Wait, row 3 c2 is 4, row 4 c2=5, row 5 c2=6.

Column 1 givens: r2=1. Row 1 c1 can't be 1,2 (row), and checks blocks. Actually, process elimination: top-left box needs 4,6; r1c1 sees down column no other blocks conflict yet. But row 6 c6=3, better: column 3 now has 5 (r2), nothing else yet.

Focus column 1: possible for r1c1. But let's find easy singles. Actually, row 3 column 1: sees row3 c2=4, c4=6? No.

Step 3: Column 6 - Quick Fills from Clues

Column 6 has many clues: r2=6, r3=5, r5=2, r6=3. Missing 1 and 4.

• r1c6: in top-right box with r2c4=2, r2c5=4, r2c6=6, r3c4=6? r3c6=5, r3c5 empty.
• Top-right box (r1-2,c4-6): has 2,4,6 (row2), 5 (r3c6). Missing 1,3.
• r1c6 can't be 2,4,5,6 in box/column. Column 6 misses 1,4 but 4 in row2 c5. So r1c6 must be 1 (only left after elim).

Place 1 in r1c6. Now top-right box misses only 3 for r1c4 or r1c5, but row1 has 2(c2),1(c6).

Step 4: Row 1 Progress - Place 6 and 4

Row 1 now: . 2 . . . 1. Missing 3,4,5,6.

• Column 3 has 5 (r2). Top-left box needs 4,6 for r1c1,r1c3.
• Look at column 2: full of 2(r1),3(r2),4(r3),5(r4),6(r5). So r6c2 must be 1 (only missing).

Place 1 in r6c2. Great chain!

Now bottom-left box (r5-6,c1-3): has 6(r5c2),1(r6c2),3(r6c6 wait no c6). r6c6=3 but that's bottom-right.

Step 5: Bottom-Left Box and Column 1

Column 1 clues: r2=1. Now r6c2=1 blocks row6. For column 1 missing: sees r2=1, r4=? r3c1 empty.

Actually, let's target naked singles. Row 4 has 5(c2),3(c4),2(c5),4(c6). Missing 1,6.

• r4c1 or r4c3. But c3 has 5(r2). Row4 c3 empty.

Row 3: 4(c2),6(c4),5(c6). Missing 1,2,3. Positions c1,c3,c5.

Key: column 5 has r2=4, r4=2. r3c5 empty, but let's find singles.

Step 6: Use Process of Elimination in Middle Boxes

Middle-left box (r3-4,c1-3): has 4(r3c2),5(r4c2). From row3 missing 1,2,3; row4 missing 1,6.

• Column 3: r2=5. No other yet.
• Try number focusing: where can 6 go in column 1? Sees r5c2=6, so not row5. Row1 c1 possible, row3c1, r4c1, r6c1.

Bottom row6: . 1 . . . 3. Missing 2,4,5,6.

Column 4 has r2=2, r3=6, r4=3. So many.

Step 7: Top-Left Completion - Place 4,6

Top-left: missing 4,6 in r1c1 and r1c3 (since r1c2=2).

Row 1 column 3 possibilities: can't be 5(col),2(row),1(c6 later). But check column 1 for r1c1 can't be numbers in row1.

Column 1 down: r2=1, r3c1 can't be 4(r3c2), etc. Actually, look at row6 column1: bottom-left needs numbers.

Let's place obvious: look at row5: . 6 . . . 2. Missing 1,3,4,5.

Column 3 row5 empty.

Key insight from clues: Row 1 c1 must be 4. Why? Because if not, check possibilities: column 1 can't have 1(r2),5(r4c2 blocks? No. Elimination: the top-left must pair 4 and 6. But row 6 c2=1, and bottom has 6(r5c2), so column 1 r6c1 can't be 6 (row5), can't be 1(r6c2), etc.

To speed: after placements, r1c1 is 4 (only fits without violating column 1 future, but logically: column 1 missing 2,3,4,5,6 (1 taken). But row1 needs 3,4,5,6. Intersect with box.

Place 4 in r1c1, 6 in r1c3 (process: can't be other way, as column 3 sees 4 elsewhere? Column 3 r4c4=3 no. Actually, standard naked pair resolution: the pair 4/6 must swap, but check column conflicts. Column 1 r4c1 sees 5(c2), but later.

Step 8: Chain Reaction - Fill Top Row and More

Row 1 now . 2 6 . . 1 wait with 4 in c1, 6 in c3. Missing 3 and 5 for c4 and c5.

Top-right box: r1c4 and r1c5 need 3 (since 1 placed,2,4,5,6 taken). No: box has 2,4,6(row2),5(r3c6),1(r1c6), so yes only 3 missing for the box, but two cells? No: top-right is r1-2 c4-6: row2 c4 empty? Row2 is 1 3 5 2 4 6, so c4=2, c5=4, c6=6. r3c6=5 but r3 is row3, top-right is rows1-2 only.

6x6 boxes: rows1-2 c4-6: clues r2c4=2, r2c5=4, r2c6=6. Empty r1c4, r1c5, r1c6=1 now. So numbers 1,2,4,6 taken, missing 3 and 5 for r1c4 and r1c5.

Now row1 has 4(c1),2(c2),6(c3),1(c6), missing 3 and 5 for c4,c5. Perfect match. Now which? Column 4 has r2=2, r3=6, r4=3. So r1c4 can't be 2,3,6. Can be 3 or 5. Column 5 has r2=4, r4=2. Can be.

To decide: look ahead, but actually place later. First, other singles.

Step 9: Middle Row Fills - Row 3 and 4

Row 3: . 4 . 6 . 5. Missing 1,2,3.

• c1: column1 now r1=4, r2=1.
• c3 empty, c5 empty.
• Column 5: r2=4, r4=2, r5=? . Middle-right box r3-4 c4-6 has 6(r3c4),5(r3c6),2(r4c5),4(r4c6),3(r4c4).

Middle-right box almost full: missing one cell r3c5, numbers taken 2,3,4,5,6 so 1 in r3c5.

Place 1 in r3c5. Awesome naked single!

Step 10: Continue Elimination

Now row3: missing 2,3 for c1 and c3 (1 placed c5).

Row 4 c3 empty, but row4 missing 1,6 for c1,c3 (others filled).

Column 3 now: r1=6, r2=5, r3=? ,r4=?,r5=?,r6=? .

Bottom-right box r5-6 c4-6: has 2(r5c6),3(r6c6). Others empty.

Step 11: Bottom Row and Column Fills

Row 6: . 1 . . . 3. Missing 2,4,5,6.

Column 4: r2=2,r3=6,r4=3. Missing 1,4,5 for r1,5,6.

But r1c4 possibilities 3 or 5 from earlier.

Place in row 3: Middle-left box r3-4 c1-3: has 4(r3c2),5(r4c2),1(r3c5 but c5 not in left). Left is c1-3.

Numbers in middle-left: 4,5. Row3 adds from missing 2,3 (1 in c5 outside). Wait.

Column 1: r1=4, r2=1, r4c2=5 blocks row, r5c2=6. So missing 2,3 for r3c1, r6c1.

Row 3 c1 can't be 4,6,5 in row/box. So 1,2,3 possible but 1 later placed elsewhere? No 1 still possible? Row3 missing 1,2,3 but 1 now in r3c5 same row! Yes r3c5=1, so row3 c1 and c3 missing 2 and 3.

Perfect pair.

Now to place: look column 1 for 2,3 in r3c1 or r6c1.

Step 12: Advanced Elimination - Pairs and Singles

Similarly, row5 missing 1,3,4,5 for c1,c3,c4,c5 (c2=6,c6=2).

Key: bottom-left box r5-6 c1-3: has 6(r5c2),1(r6c2). Missing 2,3,4,5.

Column 3 sees lots.

Place 2 in r3c1 (why? Because if 3 in r3c1, then row3 c3=2, but check column 3 r1=6,r2=5, then later conflicts, but logically: actually from source tips, focus one number.

Let's use number 2 placement. 2's in grid: r1c2, r2c4, r4c5, r5c6. So row3 must have 2 in c1 or c3.

Column 1 no 2 yet. Column 3 no 2.

But row 6 can't have 2 in c1 if ... standard way: place 2 in r3c1, 3 in r3c3.

Yes, because column 1 r6c1 will need other.

Step 13: Row 4 Fills

Row 4 now with r3 filled: row4 missing 1,6 for c1,c3.

Middle-left box now has r3c1=2, r3c2=4, r3c3=3, r4c2=5. So taken 2,3,4,5. Missing 1,6 for r4c1 and r4c3. Perfect pair.

Column 1: r1=4,r2=1,r3=2. Missing 3,5,6 but 5 in r4c2 same row no. For r4c1 possibilities 1,6 from row, but column 1 can't have 1,2,4 taken, so 3,5,6 possible but row limits to 1,6 so 6 in r4c1 (1 blocked by r2c1).

Place 6 in r4c1, then 1 in r4c3.

Step 14: Top Row Completion

Now column 3: r1=6, r2=5, r3=3, r4=1. Missing 2,4 for r5c3, r6c3.

Row 1 c3=6 already. Now for r1c4 and c5: 3 and 5.

Column 4: r2=2, r3=6, r4=3. Missing 1,4,5.

Column 5: r2=4, r3=1, r4=2. Missing 3,5,6.

r1c4 in column 4 can't be 2,3,6 taken, so from 3,5 must be 5 (3 would be ok? 3 not taken in col4, r4=3 yes taken. r4c4=3 yes. So can't 3, must 5 in r1c4.

Then 3 in r1c5.

Step 15: Bottom Fills - Row 5 and 6

Row 1 complete: 4 2 6 5 3 1.

Now row 5: . 6 . . . 2. Missing 1,3,4,5.

• c1: column1 now r1=4,r2=1,r3=2,r4=6. Missing 3,5 for r5c1,r6c1.
• Bottom-left: needs 2,3,4,5 but 1,6 taken. Wait has 1,6 taken yes missing 2,3,4,5 for four cells: r5c1,c3; r6c1,c3.

Column 3: r1=6,r2=5,r3=3,r4=1. Missing 2,4 for r5c3,r6c3.

Row 5 c3 can't be 6(row),2(row c6). So from 2,4 must be 4? Wait possibilities for r5c3: column limits to 2,4; row misses 1,3,4,5 so 4 possible.

Actually place: row 6 c3 must pair.

Bottom-right box r5-6 c4-6: has 2(r5c6),3(r6c6). Missing 1,4,5,6 for r5c4,c5; r6c4,c5.

Column 4 missing r5c4,r6c4: column4 has r1=5,r2=2,r3=6,r4=3 so missing 1,4.

Column 5: r1=3,r2=4,r3=1,r4=2 missing 5,6 for r5c5,r6c5.

Naked single: row5 now, c1 possibilities: column1 missing 3,5. Row5 missing 1,3,4,5. Intersect 3,5. But more.

Continue: place 3 in r5c1 (column1 pair 3,5; but check box. If 5 in r5c1, then r6c1=3, but row6 missing 2,4,5,6 wait 5 would be ok? But later conflict.

Logically: row5 c4: column4 missing 1,4. Row5 possible 1,3,4,5 so 1,4.

Similar for others. Place 3 in r6c3? No.

Row 6 c5: column5 missing 5,6. Row6 missing 2,4,5,6 so 5,6 possible.

Strong logic: since column3 missing 2,4 exactly for r5c3 and r6c3.

Bottom-left needs 2,3,4,5. But 2 must go somewhere. Column1 needs 3,5; no 2 or 4 there since missing only 3,5.

So 2 and 4 must be in c3 of bottom rows. But column3 is 2,4 exactly! Perfect, so r5c3 and r6c3 are 2 and 4.

Now which? Row5 has 6c2,2c6 so can't have 2 again, so r5c3=4, r6c3=2.

Step 16: Final Fills

Now row6: . 1 2 . . 3. Missing 4,5,6.

Column1 r6c1: now only 5 left (3 would be, but since r5c3=4, wait column1 missing 3,5 still both open? No with r5c1 not placed.

Bottom-left cells left: r5c1, r6c1. Numbers left for box: since c3 has 4(r5),2(r6), and has 1(r6c2),6(r5c2), so missing 3,5 for r5c1 and r6c1. Matches column1 exactly.

Row5 remaining cells c1,c4,c5 missing 1,3,5 (4 placed c3, 6c2,2c6).

Row6 c1,c4,c5 missing 4,5,6 (1c2,2c3,3c6).

r5c1 possibilities: 1,3,5 from row, 3,5 from column/box. So 3 or 5 (1 not in column1 possibles? Column1 missing 3,5 yes, 1 taken long ago.

1 not possible in r5c1 column.

To decide: look r5c4 column4 missing 1,4.

Row5 possible for c4:1,3,5. Intersect 1.

So 1 must be in r5c4! Naked single for position via elimination.

Place 1 in r5c4.

Now row5: c1 ?, c5 ?, c3=4, c4=1. Missing 3,5 for c1,c5.

Column5 r5c5: column5 missing 5,6. Row5 3 or 5, so 5 in r5c5.

Then 3 in r5c1.

Now column1 r6c1: only 5 left.

Row6 now: 5 1 2 . . 3. Missing 4,6 for c4,c5.

Column4 r6c4: column4 missing 4 (since 1 in r5c4).

So 4 in r6c4.

Then last 6 in r6c5.

Verify all rows, columns, boxes complete with 1-6 unique. Puzzle solved!

This LinkedIn Mini Sudoku #161 (Nineteen) used basic techniques like naked singles, pairs, and elimination, building chains from fullest rows. Practice daily for faster solves. Check the solution grid via the link for confirmation.