NYT Hard Sudoku Walkthrough | July 21, 2026

[00:00:00]Hello. Let's do the New York Times hard sodoku for July 21st, 2026. There's a link in the description if you'd like to try the puzzle yourself. And I'm going to get started right now. Right.

[00:00:11]Starting with this two and five.

[00:00:13]Uh the two twos look in here. This two helps in a very nice way, causing us to place the two in this box. These two twos look in putting a two in one of these two.

[00:00:24]All right, the fives look down. Placing the five in this box. We just filled a box column. Let's look at these other digits to see if any aren't yet placed in the box. We have 2, three, and five.

[00:00:33]They're all placed. We are down to four digits, though. So, I'm going to look at this anyway. Uh, we can see the eight looks in, including the eight in one of these two. And so, these are down to 1 47. And unfortunately, these are all of 1478. So, we're not going to pencil those.

[00:00:50]The eights do point in here, though, with this eight. This eight looks down.

[00:00:53]Puts an eight one of these two. All right, that was the two and the the five vertically. We have the five horizontally with this five. Putting a five in one of these two. All right, let's move on. We have the one here. Two ones look down. Puts a one in one of these three.

[00:01:10]Um, we have the fours looking back. Putting a four in one of these two. We had a prime opportunity to limit four, but unfortunately there's no four over here.

[00:01:21]All right. vertically. I don't see anything with four. We have the six.

[00:01:28]Two sixes. Look down. Six. Looks in six and one of these two.

[00:01:32]Um, I don't see anything there. How about the eight?

[00:01:36]I don't see anything. Anything in this row or this column? Well, this column's empty. This row has a four, which is already placed. So, it's primed for something looking through here or through here, but we don't have that right now. We'll keep an eye out. We have the three, four, five, and seven.

[00:01:51]There are no repeats in this column in this stack. We do have a filled box column though. And then the 1, eight, and nine. Because there's no repeats, it makes the 1, eight, and nine really powerful. In fact, the eight is placed.

[00:02:01]Placing the eight here. These two eights look back. Putting an eight one of these two. And now eight in this column is one of these two.

[00:02:10]That's handy. So these can't be eight because this column needs an eight. It's going to place it here or here. We say that claims we claims the eight. Column one claims the eight from box four.

[00:02:20]meaning the rest of box four can't be an eight.

[00:02:24]All right. Um and then the one looks up placing a one which gives two ones here.

[00:02:28]One and one of these three. And now this is just a triple. It's the uh two 69. That's not two. That's not six.

[00:02:40]Okay. Um I don't think there's anything else to do. Well, the nine looks down.

[00:02:45]269 says not here. Nine looks in. So nine's one of those two.

[00:02:53]Okay, I do have 269 here and 269 here.

[00:02:59]Just need one more digit limited there.

[00:03:00]And we've got a hidden quad.

[00:03:05]Okay. Well, nothing there yet. This row is down to four digits. We need the 2 479.

[00:03:13]These can't be This can't be 27 or nine.

[00:03:15]So, this is a naked four.

[00:03:17]Um, can we follow up on that? I'm going to fill out the 279 here first. That's not a two. All right. Um, this column is down to one four eight. Not four.

[00:03:32]Obviously, not four. 168.

[00:03:35]This can't be one or six. So, this is a naked eight. And that makes a one six pair here. Oh, this can't be one. It sees one in the row. That's six. And that's one. Very nice. Whole column is done. I don't need to follow up on these because I haven't scanned those bands yet. But, uh, I did get the one, I got the four. Anything else?

[00:03:54]This row is down to 3 6 8 9. This can't be three or six. So, this is 89.

[00:04:05]This is any of them. Any of them. Oh, this can't be eight. This is 369. Oh, it's not six either. Can't be six or eight.

[00:04:11]39 only. All right. Okay, I also want to look at this box right away. We need a 1 49.

[00:04:19]Oh, yeah. The one looks in. Oh, no. The two ones look in. Placing a one. And then this is a 49 pair. That four nine pair says that can't be nine. So, that's seven. Getting a two nine pair. That's not seven. That's not one. So, we should be able to So, seven's one of these two.

[00:04:36]One's one of these two. We should be able to pencil now. So, we need one 48 and one uh this can't be one. Sorry.

[00:04:42]This is 78 only. No, it's 4 7 8. I I thought about that wrong. 4 7 8 9. This can't be eight or seven or four. So, this is a naked nine. That's eight.

[00:04:56]Four seven pair. So, this is one and eight. That's not a one. And then up here. Oh, here it's not a nine. Okay.

[00:05:03]Here we need a pair. It's three and six.

[00:05:10]All right.

[00:05:14]We got a whole lot of stuff. Um, I don't think I want to look at these yet. Did Does anything look through here? One. Nine. The nine does. So, nine's in one of these two. That points down. This nine looks in. Placing the nine in this box. Got the four and the nine here. And the nines's point down with this nine. This nine looks in.

[00:05:33]Putting a nine in one of these two.

[00:05:34]That's quite handy.

[00:05:38]Uh, so that was the nine. The eight and the four are already placed. Okay.

[00:05:52]Okay. Um if we either this is going to be a three or this is going to be a two, right?

[00:06:03]Because they can't both be nine. If it ends up at three, we're going to place the three here. Just thought I'd point that out. Um I think I want to look at this band which is like almost done. Um the ones the twos we have the fives. So five is one of these two. Six is in one of these two. And that means six is one of these two in this column. So we can't place any sixes here. Really here. It's where it's eliminated from because we already have this six. Um and then we've got the nines.

[00:06:33]Four digits left in this box. But I'm going to do the three left in this row first. We need a two four seven. This isn't two. So, this is 47.

[00:06:43]This can't be four or seven. So, that's two. Leaving 47 behind.

[00:06:50]Um, let's just do this box then. We have 1 two. We need a 3 478.

[00:06:58]Well, the seven looks in. Putting a seven in one of these two. So, these are 3 48. That's not a four. So, the four is in one of these. two that points down with this four. Four is one of these. And we also said the seven points the seven points up which is helpful. Put a seven one of these two.

[00:07:16]Oh, I missed these sevens.

[00:07:18]Okay.

[00:07:21]Um how about these? We need 3 4 6 8. This can't be three or four. So this is 68.

[00:07:31]This is 3 4 6.

[00:07:34]These four digits are a 3578.

[00:07:38]This can't be five. So this is 378.

[00:07:41]This can't be five or eight. So this is 37. [clears throat] This can't be 37. So this is 58. This is 357 because it's not eight. Interesting.

[00:07:51]Um well, I got it all penciled for what it's worth. Oh, I have this 269. I should pay attention. So that can't be six. That places the six here.

[00:08:03]Okay.

[00:08:08]The only thing to see down here is the eight. So we already have marked. Let's look at this column here which is down to four digits. We need a 3457.

[00:08:17]3457. Well, but this isn't four. This is 357.

[00:08:22]This is 457.

[00:08:24]This is 347.

[00:08:26]This is any of them. Okay. Not helpful.

[00:08:29]What about this column? It's down to one, two, five. not two 1 five 8 9.

[00:08:36]This this can't be five or eight. So this is a naked nine.

[00:08:40]And so we're down to one five here and 158 here. Oh, sorry. Eight's not in the box. So eight goes here. So one five pair. That's not eight. This nine actually resolves the nine in this box.

[00:08:51]I said this wasn't eight. I don't know what I did. Hold on. Did I do something else instead?

[00:08:56]Whoa. I didn't mean to press that.

[00:08:59]I'm right so far, though. Okay, so the five in this row goes here now that this eight is placed.

[00:09:06]And then we have a 3 seven pair here.

[00:09:11]Uh this column is down to 3 47.

[00:09:17]That one's not three.

[00:09:24]This is a 47 pair. So that places the seven here. No, sorry. Places the five here. Let's get it right. That's one and five. That's not a one. Placing the one and the eight in this box, giving us the three. The five looks up, giving us the five in this box. Down here, we get the seven, four, and eight. Here we get the four, seven, three. That's seven and three. That's four and seven. That's not a seven. The seven's placed here with this four. That's three. We get the seven, 9, and two. So, we didn't end up with three here, but the three still ended up here anyway.

[00:09:55]Uh, that's six and three. That's nine, two, and six.

[00:10:00]All righty.

[00:10:02]Just need a few more digits here. Uh where's where the twos go? Is this the way to do it? Probably not. What's this triple? We need a two 4 six. So the four goes here. This is a two six pair. That means this Oh, and this two looks down.

[00:10:18]So that's six and two and six. And then I need this two and this three. And we're done. All right.

[00:10:25]Cool. Not too bad today. Um, it really kind of just solved I I I don't Maybe the pair in this row. I don't know.

[00:10:31]There wasn't all that much hard to find, was there? All right. Well, how'd you do?