The Best Free Offline Sudoku and Crossword Apps (Tested With the Wifi Off)

The short version: for sudoku, download AGED Sudoku or Sudoku.com and grab the offline puzzle pack before you travel; for crosswords, Simon Tatham's Puzzle Collection and the free daily Puzzle Page crossword are the two that load with no bars showing. Most "free offline" apps in this space are only half-offline, and I found that out the hard way on a delayed flight from Tel Aviv.

Why this list exists

I searched "best offline sudoku apps" before a trip last year and installed four of the top results while I still had airport wifi. Two of them refused to open a single new puzzle once I switched to airplane mode. One showed me a full-screen ad request and just sat there, spinning, waiting for a connection that wasn't coming. That three-hour delay taught me more about which apps are truly offline than any review page had.

So this isn't a list built from app store descriptions. It's built from turning the wifi off on purpose and seeing what still works.

What "free offline" means in an app store listing

Here's the bit most roundups skip. When an app says "play offline," it usually means one of three things, and they are not the same:

• The puzzles are stored on your phone permanently, no connection ever needed again (rare, but it exists).
• The puzzles download in a batch the first time you open the app with wifi, and you're offline after that until you run out (common).
• The app opens fine offline but wants to show you an ad before you can start a new puzzle, and it will freeze or nag until it gets one (very common, and annoying).

The third category is where most of the free, big-name apps sit. They're not lying exactly, they just don't tell you that "offline" has a battery life. Sudoku.com, for example, is fine offline for solving puzzles you've already loaded, but new content and hint unlocks often want a connection to serve the ad that pays for the hint.

Best free offline sudoku apps

AGED Sudoku

This is the one I now recommend first. It's built by a solo developer, has no account, no login, and no ads at all, and every puzzle generates on the device itself rather than pulling from a server. That means it works with the phone in a Faraday bag if you really wanted to test it. The interface looks dated, hence the name, but it does the one job you want: nine grids, pencil marks, undo, done.

Sudoku.com by Easybrain

The most downloaded sudoku app on both Android and iOS, and it's well designed. Go into settings before you travel and there's a "download for offline" toggle that grabs a batch of puzzles across all five difficulty levels. I've had it hold about 200 puzzles offline without issue. The catch is the daily challenge and streak features want a connection, so you lose the calendar gamification bit if you're cut off, but the core solving works.

Simon Tatham's Puzzle Collection

This deserves more attention than it gets. It's a free, open source set of over 40 logic puzzles including sudoku, and it was built originally for desktop before being ported to Android and iOS. Every single puzzle generates locally, there is no ad code in it at all, and it's the closest thing to a guarantee that it will work with zero signal, because there is nothing in the app that has ever needed a server. It's on F-Droid and the app stores under "Simon Tatham's Portable Puzzle Collection."

Sudoku - Classic Puzzle Game (various small developers)

Worth a mention because there are dozens of near-identical apps with this kind of name, mostly from small studios in Eastern Europe and India, and the quality varies wildly. The trick is to check the permissions before installing: if a basic sudoku app is asking for location access, that's a sign it's an ad-network-heavy build, and those are exactly the ones that stall offline.

Best free offline crossword apps

Crosswords are the harder category, because a decent crossword needs a clue database, and clue databases are usually stored server-side to save space on your phone. That's why offline crossword apps are rarer than sudoku ones.

Puzzle Page Crossword

Free daily crosswords, and once a puzzle has loaded it stays cached on the device, so if you open it with wifi in the morning and lose signal later, that day's puzzle is still solvable. New puzzles for future days do need a connection to fetch, though, so it's a same-day offline app rather than a stockpile-a-week-ahead one.

Simon Tatham's Puzzle Collection (again)

It includes a word-grid style puzzle but not a true clued crossword, so it's not a full substitute here, just worth knowing it exists in this category too if you want a break from numbers.

Crossword Puzzle Free (Boppin Games and similar)

A handful of small studios publish offline crossword packs, usually themed (general knowledge, quick, cryptic-lite), where the entire word bank ships inside the app install rather than being streamed. Look for apps that state an install size over 40MB for what should be a simple word game, that's usually a sign the clue database is bundled in rather than pulled live.

NYT Crossword (the free tier)

Worth including because so many people assume it's fully offline once downloaded, and it isn't reliably. The free Mini crossword needs a connection to fetch each day, and while the full archive is available to subscribers with some offline caching, the free version is the least offline-friendly app on this whole list. I'd only use it when I know I've got signal.

The real test: a flight, a broadband outage, and what held up

The flight I mentioned earlier was BA from Tel Aviv, delayed on the tarmac for close to three hours with the seatbelt sign on and no wifi purchase option working. I had six puzzle apps on my phone. Sudoku.com worked because I'd downloaded a pack the night before. AGED Sudoku worked without me having done anything at all, since it generates fresh every time. Puzzle Page crossword worked because I'd opened that day's puzzle over the airport wifi twenty minutes earlier. Two other sudoku apps and the NYT Mini all sat there asking to reconnect.

Separately, my broadband went down for three days last winter (a cut cable during roadworks two streets over, the provider told me), and it was the same pattern: apps that store puzzles locally kept going, apps that rely on a live ad call or a cloud save stalled within a day of use. If you want a general sense of what else survives a dead connection, I've done a wider round-up of free games to play offline and online that covers this same problem across more genres, not just puzzles.

How to set an app up before you need it offline

This takes about five minutes and it's the bit people skip:

• Install the app while connected to wifi, not mobile data, so the initial puzzle pack downloads fully rather than half-loading and giving up.
• Open settings inside the app and look specifically for "offline mode," "download puzzles," or "offline pack," not all apps put this on the home screen.
• Solve one puzzle straight after downloading, while still connected, so any first-run ad or verification step is out of the way.
• Turn on airplane mode and try opening a fresh puzzle before you travel, not after. If it stalls, you've found out at home instead of at 30,000 feet.
• Check the puzzle count in settings. If it only shows "10 puzzles remaining," that's your entire offline supply for a long flight, top it up while you still have signal.

The trade-off nobody quite says out loud

Here's the uncomfortable bit. The apps that are 100 percent reliably offline, no ads, no login, no server dependency at all, tend to be the least polished ones. AGED Sudoku and Simon Tatham's collection look like they were designed in 2009, because in one case it more or less was. The apps with beautiful themes, smooth animations, daily streaks, and achievement badges (Sudoku.com being the best example of this done well) get that polish paid for by an ad and analytics layer, and that layer is exactly what breaks when you're offline. You are choosing between an app that looks lovely and needs the internet more than it lets on, or an app that looks like a spreadsheet and will never once let you down. I've settled on keeping one of each on my phone rather than pretending one single app does both jobs.

This same tension shows up across the whole offline puzzle category, not just these two genres, which is why I put together a separate piece specifically on offline puzzle games tested on real flights if crosswords and sudoku aren't quite your thing and you want something with more variety for a long journey.

Why bother with sudoku and crosswords specifically, over other puzzle types

I'm 53, and somewhere in the last decade sudoku and crosswords stopped being "a train thing my dad did" and became one of the few times my brain feels quiet. There's research behind why puzzle games in general seem to matter more to adults than we give them credit for, and I've written before about why puzzle games are popular with adults and what they build in your brain, but sudoku and crosswords specifically hit two different systems: sudoku is pure logic with no language involved, crosswords pull on vocabulary and general knowledge, and switching between the two on a bad day does more for me than sticking to one.

If what you're after is stress relief rather than a mental workout, it's worth reading how adults use puzzle games to relieve daily stress, because the offline angle matters less there than the habit itself does.

What I'd install today if I were starting from nothing

Two apps, not six. AGED Sudoku for guaranteed offline sudoku with zero fuss, and Puzzle Page for a daily crossword that will hold up for a full day without signal as long as you open it once in the morning while connected. That's it. Everything else on this list is worth trying, but those two have never once let me down, and I've now tested them across four long haul flights and one very annoying broadband outage.

If you'd rather not deal with downloads and offline packs at all and you've usually got a connection anyway, it's worth knowing where the browser-based option sits too, and I've mapped that out separately in a piece on free online games that don't need downloads, which covers the trade-off between install-free convenience and true offline reliability from the other direction.

Related: writing for us on mobile apps.

I've rounded up the best free offline word games to play anywhere.

Frequently asked questions

Is Sudoku.com free with no hidden cost?

Yes, the core game is free and ad-supported, with an optional paid subscription that removes ads and unlocks extra themes, but you never need to pay to keep solving puzzles.

Do I need wifi every time I open a sudoku app?

No, not if you've downloaded an offline pack in advance. Most reliable sudoku apps let you generate or store dozens of puzzles locally, so you only need a connection occasionally to top the pack back up.

Why do so many crossword apps stop working without internet?

Because the clue and answer database usually lives on the app's server rather than being stored on your phone, to keep the install size small, so new puzzles specifically need a connection even when the app itself opens fine offline.

Which app is best for a long flight with no wifi at all?

AGED Sudoku for sudoku, since it generates every puzzle on the device, and Simon Tatham's Puzzle Collection if you want variety, since neither has ever needed a server connection in the years I've been using them.