12FocusThe Great Lock In and how to start late
The Great Lock In is a TikTok challenge: you spend the last four months of the year, September 1 to December 31, on the goals you would otherwise save for January. There are no official rules, so you write your own: one to three goals, a daily action for each, and a smaller version for bad days.
Starting in November? You haven’t missed it. You start smaller.
Updated
When does the Great Lock In end?
On December 31. Most posts start it on September 1, which makes it 122 days. Some creators began in August; there is no official date (Pedestrian, Know Your Meme).
Counted from your phone’s date, today included. Running a Winter Arc as well? It covers the same stretch from October 1. For weekdays and weeks to December 31, see how many days are left in the year.
days left
- 8 weeks and 6 days until December 31
- Day 61 of 122 since September 1
- As of October 31, 2026
What is the Great Lock In?
A self-improvement challenge that took off on TikTok in August 2025 (Know Your Meme). “Lock in” is slang for focusing on one important thing without distraction. The challenge asks you to do that for the last four months of the year instead of waiting for New Year’s resolutions (Cal Newport).
It came back in 2026 with the same dates. People lock in on fitness, saving money, reading, sleep, getting organised, and, in 2026, mental wellbeing too (BuzzFeed).
What are the Great Lock In rules?
There are none you have to follow; every creator posts their own. These five are written for an ordinary Tuesday, not for day one:
- One to three goals, written as results. “Read six books by December 31”, not “read more”.
- One daily action per goal, with a time. “Twenty pages at 9:30 pm.” Plans that spell out when, where and how had a medium-to-large effect on reaching goals across 94 tests (Gollwitzer and Sheeran, 2006).
- A floor for bad days. The smallest version that still counts: five pages. On a bad day you do the floor, not nothing.
- A phone rule, decided in the morning. How long the feed gets, and that it comes after the action.
- A weekly check on the same day. Count the actions you finished, change next week’s plan, keep the goal.
Is it too late to lock in?
No. September 1 is a social media convention, not a deadline. What helps is a date that feels like a new start: in three field studies, Google searches for “diet”, gym visits and commitments to goals all rose after the start of a new week, month or year (Dai, Milkman and Riis, 2014). So start on the next Monday or the 1st of the month.
Starting late changes the size, not the rules. In November, take one goal instead of three and give it every day. And don’t stop on December 31: a new daily habit took 66 days on average to feel automatic, from 18 to a predicted 254 (Lally and colleagues, 2010). Twelve weeks from early November ends in late January; the date is easy to find.
What goes in your lock-in rules?
Five lines. Fill them in here, then copy them into your notes or onto your lock screen. What you type stays in your browser.
Want a box to tick for every day until December 31? Use the free daily tracker; it works for the Great Lock In too.
How do you lock in with a phone?
You decide before the feed does. Cal Newport reads “lock in” as a reaction to phone distraction, and argues that a positive alternative works better than a warning. So the phone rule should point at the action: the feed comes after the twenty pages, not instead of them.
That is the deal 12Focus makes on iPhone and Android. You give the apps you choose a daily allowance; each planned action you finish adds minutes. When the allowance runs out, those apps pause until midnight. Prefer the free route? Here is how to block social media with the settings you already have.
Is there an app for locking in?
12Focus is built for a stretch like this. It holds up to three goals for a 12-week cycle, turns each week into a few actions with days, and shows today’s on one screen. The week closes with a short review where you choose next week’s actions.
A 12-week cycle started now carries the lock-in past New Year’s Day, so January is the middle of something, not another start. Plan the twelve weeks first if you like.
What people ask about the Great Lock In
Is the Great Lock In only for fitness?
No. People lock in on saving money, reading, sleep, getting organised, school and work as well as fitness. Pick the goal you would otherwise write on a New Year’s list. Locking in on school? Here is how to lock in on studying.
Is the Great Lock In the same as a Winter Arc?
Close. Both use the end of the year to get ahead of January, and both end on December 31. The Great Lock In usually starts on September 1; a Winter Arc on October 1. Pick either name; the plan is the same.
How many goals should I lock in on?
One to three. A doctor quoted by BuzzFeed advises a few achievable goals that fit around the life you already have. With less than two months left, one goal done every day is enough.
What if I miss a day?
Carry on the next day at the planned size. In a 12-week study of 96 people building a daily habit, missing one opportunity did not materially affect habit formation (Lally and colleagues, 2010). There is no day one to go back to.
Do I have to post my Great Lock In on TikTok?
No. Writing your progress down is what helps: in a meta-analysis of 138 studies, monitoring progress helped people reach their goals, and helped more when it was recorded or reported to others (Harkin and colleagues, 2016). One person you chose is enough of an audience.
Can I start the Great Lock In in November or December?
Yes. The dates are a social media convention, not a deadline. Start on the next Monday or the 1st of the month, pick fewer goals, and keep going into January instead of stopping on December 31.
Lock in before the year runs out
12Focus holds up to three goals for a 12-week cycle, turns each week into a few actions, and closes it with a short review.