Let me confess something a little creepy.

I have a habit of peeking at other people's dev posts.

Not stealing the writing — relax. I run a tiny read-only job that fetches the public pages on dev.to, Zenn, and Qiita and counts only the boring parts: titles, post times, like counts. Who published what, at what hour, and how far it traveled. Then it tallies the lot.

The reason is petty: my own posts weren't landing. The content is already in my hands — so I wanted to know how much the rest, the when and how you publish, actually moves the needle. By the numbers, not by gut.

So I counted across three platforms. And the conditions that make a post fly turned out to be roughly mirror images between Japan (Zenn / Qiita) and the English-speaking world (dev.to). Here's the story.

First, my most important disclaimer

This post is full of numbers, so let me put up a guardrail before any of them.

This is correlation, not causation. A result like "weekend posts don't do well" could mean the weekend itself is bad — or it could mean people who post on weekends are just dashing something off on the side. The data can't separate those. Please read it that way.

Also, I only keep aggregate numbers I computed myself. I don't store or reuse anyone's article body (read-only GET, count the features, throw the page away). I peek, but only at the overall shape. Nobody gets singled out here.

With that out of the way — four findings I enjoyed.

1. The best hour to publish is just your readers' time zone

This one came out cleanest.

• On Qiita, posts published in the morning win (+32pt in the GOOD group). Midday is +14pt. Evening is -32pt, late night -14pt.
• Zenn likes midday too (+27pt). Late night is -15pt.
• dev.to is the exact opposite. Late night Japan time scores +7pt — Japanese evening is actually weak.

The trick is obvious once you see it. dev.to's readers are English-speaking, mostly US. Late night in Japan is the US working day. Zenn and Qiita readers are in Japan, so the Japanese morning-to-midday slot just works.

So the right answer to "when should I publish?" isn't the platform — it's which time zone your readers live in. English version in the dead of Japanese night; Japanese version in the Japanese morning. Obvious in hindsight. Still satisfying to watch it fall out of the data.

2. On weekends, Japanese posts die

This one honestly spooked me a little.

Zenn posts published on weekends score -54pt. Only 15% of the GOOD group went out on a weekend; 69% of the BAD group did. Qiita is -25pt too.

Meanwhile dev.to is -6pt — basically noise.

The funny part: the Japanese platforms have more weekend posting, yet those posts don't travel. Everyone writes on Saturday, ships on Saturday, and sinks. Sound familiar? (It does to me.)

This follows straight from finding 1: Japanese engineers seem to read dev posts around the weekday commute and the start of the workday. On weekends they're the ones writing code, not reading about it.

And this is the textbook "correlation, not causation" trap. Weekend posts might simply be lazier than the ones people sweat over on a Tuesday. Maybe the day isn't cursed at all. But the direction is unambiguous: shipping a Japanese dev post on the weekend is playing on hard mode.

3. Numbers and colons travel differently across the ocean

Title craft splits by platform too.

• A digit in a Zenn title costs -35pt. "3 ways to…", "the 2026 edition" — those just don't fly.
• On dev.to a digit is basically nothing (-2pt). Don't sweat it.
• The colon format ("X: Y") is a headwind on all three (dev.to -14pt, Zenn -15pt). I thought it looked sharp. Readers disagree.
• For good measure, Zenn dislikes bracket titles (【】, []) at -23pt.

The only thing mildly positive everywhere was the question-form title (dev.to +7pt, Zenn +8pt, Qiita +7pt). Ask, and people can't help clicking. This post's title is a question. Subtle, I know.

4. Shorter usually wins

Last one is simple. Shorter posts travel further.

Zenn's GOOD group runs about 6,700 characters in the body; the BAD group about 11,700. The posts that landed are nearly half the length. Titles too — all three platforms have shorter titles in the GOOD group.

"Write more and it'll get through" turned out to be a fantasy. My hands are slowing down as I type this. (This very post could probably stand to be cut.)

The four times the numbers almost fooled me

I've been saying "X works" — but when you tally things, fake correlations show up constantly. Here are the four I tripped over. Without this section, this whole post is just a pile of dangerous claims.

1. Emojis work — no they don't.
On Zenn, "title has an emoji" was 100% in both the winners and the losers. For a second I thought "emojis are mandatory?!" — but Zenn requires an emoji in the frontmatter. If everyone does it, it can't explain a difference. A metric that's structurally saturated looks like signal and is pure noise. Writing "emojis work" would have been a great way to embarrass myself.

2. "Japan engages more" is a misread.
By median likes, dev.to is 1 and Zenn is 3. Tempting to read "Japan engages harder!" But that's just different platform sizes and different like-cultures — comparing absolute values across countries is meaningless. Look at the shape. Zenn's top 10% reaches 74 likes; dev.to's reaches 13. Same word "viral," totally different ceiling. Never brawl with raw absolute numbers.

3. The sample is small.
Zenn's winning group is 26 posts. Shouting "-54pt!" off 26 posts is, frankly, scary. Each platform has its own cutoff and its own sample size (Zenn 26, Qiita 28). So I don't call any of this a "law" — I file it as an observed hypothesis and only promote the ones that reproduce in another week. A number seen once is still a horoscope.

4. And all of it is just correlation.
I'll say it one more time. Whether weekends are weak, whether long posts are weak — the data can't tell me if the condition is bad or if the people who post under it are just careless. Numbers point a direction; they don't guarantee the reason.

Counting kills your instincts, one at a time

What it really taught me is that this was never a hunt for a growth hack.

It was the opposite — a slow execution of every gut feeling I'd been carrying. "Surely emojis help." "Surely a digit gets the click." One by one, the things I vaguely believed got quietly voted down as I counted.

What survived is a few plain lines. English version in the dead of Japanese night; Japanese version on a weekday morning. Short, and ideally a question. That's it.

No secret hack. But I got to drop a stack of instincts I'd been trusting without ever checking them. Before you fight on content, at least don't trip over your own feet in the delivery. Next time your post mysteriously won't land — go count. (And lose your instincts one at a time, same as I did.)