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Oh Dear uptime report, 2025 data

The state of website uptime.

We looked at 1,817,403 real outages on tens of thousands of sites. Most are over in two minutes. A few run for hours, and those do the damage.

How we measured this
oh dear Uptime report March to December 2025
98.71%
average uptime, all monitored sites
1.9 min
median time to fix an outage
98.6%
of outages fixed within the hour
61.4%
of sites had at least one outage

Real monitoring data, added up and anonymous

1,817,403 outages Confirmed from 2 locations Updated every year

How long outages last

Most outages are over in two minutes.

98.6% are fixed within the hour. The 0.3% that run past six hours are the ones that hurt.

Time to fix an outageThe average is 12× the median. A few very long outages pull it up.
of outages
Fixed within the hour98.6%
1 to 6 hours1%
Over 6 hours0.3%
Median1.9 min
Average21.9 min

When outages start

Downtime doesn't keep office hours.

67.7% of outages start on a weeknight or at the weekend, when fewer people are watching.

Outages started, by day and hourEach square compares one hour with the average hour of the week. Times are local to each site.
00:0001:0002:0003:0004:0005:0006:0007:0008:0009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:0022:0023:00
Mon1×0.9×0.9×0.9×0.8×0.8×0.9×1×1.2×1.1×1.1×1.1×1.1×1.1×1.1×1.1×1.1×1×1×1×0.9×0.9×1×1.1×
Tue1.1×0.9×1×1×0.9×0.9×1×1.1×1.3×1.2×1.2×3.2×3×1.6×1.5×1.2×1.2×1.1×1×1×1.1×1.1×1.2×1.1×
Wed1.2×1×1×0.9×0.9×0.9×1×1.1×1.3×1.3×1.2×1.1×1.2×1.1×1.1×1.1×1.1×1×1×0.9×1×0.9×1.1×1×
Thu1.2×1.1×0.9×1×0.9×0.9×1×1.1×1.2×1.1×1.1×1×1.1×1.2×1.1×1×1.1×0.9×1×1×0.9×0.9×1×1×
Fri1×0.9×1×0.9×0.8×0.8×0.9×1×1.3×1.1×1.1×1.1×1.1×1×1×1×1×1×0.9×0.9×0.9×0.9×0.9×0.9×
Sat1×0.9×0.9×0.8×0.8×0.8×0.7×0.8×0.9×0.8×0.8×0.8×0.7×0.7×0.8×0.8×0.8×0.8×0.8×0.8×0.8×0.8×0.9×1×
Sun1×0.9×0.9×0.9×0.8×0.8×0.8×0.8×0.9×0.8×0.8×0.8×0.8×0.8×0.8×0.8×0.9×0.8×0.8×0.9×0.8×0.7×0.9×0.9×
Share of outagesBusiness hours are 09:00 to 18:00 on weekdays, in the site's own timezone.
of outages
Business hours32.3%
Weeknights44.3%
Weekends23.4%

How often

Most sites go down at some point.

61.4%
of sites went down at least once
47
outages for the average site in 10 months
32
of those started outside business hours

Speed

Online isn't the same as fast.

The median site answers in 159 ms. One request in 20 takes over a second.

Full response time, all HTTP sitesDNS, connect, TLS, server time and download, added up.
response time
Median159 ms
90th percentile801 ms
95th percentile1,244 ms

Lighthouse, the last 6 months

Mobile is where sites fall behind.

Audit Desktop Mobile
Performance 78/100 57/100
Accessibility 89/100 90/100
SEO 91/100 95/100
First paint 832 ms 2,347 ms

The nines

What each uptime target allows.

99.9% sounds great. It still allows almost nine hours of downtime a year.

Uptime target Downtime a year Downtime a month
99% 3.65 days 7.2 hours
99.9% 8.8 hours 43.8 minutes
99.95% 4.4 hours 21.9 minutes
99.99% 52.6 minutes 4.4 minutes
99.999% 5.3 minutes 26 seconds

The cost in people

Nights and weekends.

67.7% of outages start outside business hours. Each one is an evening someone loses. Over a year, that's how good teams burn out.

The cost in money

Depends on your size.

For a small SaaS, an hour down costs a few hundred euros and some lost trials. For a big shop in the middle of a sale, it costs six figures.

Six-figure estimate: Uptime Institute outage analysis

Beyond uptime

A site can be up and still broken.

Broken links

2.9%

of the average site's links lead nowhere

Dead links frustrate visitors and hurt your search ranking.

Mixed content

2.9%

of HTTPS sites loaded at least one insecure file

One insecure file removes the padlock from an otherwise secure page. Visitors stop trusting it.

Domain expiry

0.7%

of domains came within 10 days of expiring

An expired domain takes the whole site down. It's also the easiest outage to avoid.

Scheduled tasks

23.3%

of cron jobs failed or missed a run in the last 30 days

A backup that quietly stops running goes unnoticed. You find out the day you need it.

Method

Real checks, not a survey.

Every number comes from Oh Dear's own monitoring, March to December 2025.

  1. Checked every minute

    Every site gets an HTTP check every minute.

  2. Confirmed from a second place

    When a check fails, a second location checks again. It only counts when both agree.

  3. Timed from fail to fix

    An outage runs from the first failed check to the first good one. Failures shorter than a minute are left out.

  4. Local time for each site

    Business hours means 09:00 to 18:00 in the site's own timezone.

Lighthouse scores cover the last 6 months. The scheduled-task figure covers the last 30 days.

Writing about uptime?

Copy this whole report as Markdown and paste it into your AI tool. Quote any figure, with a link to this page.

Questions about uptime.

Good targets, how uptime is calculated, and how to use these numbers.

What is a good uptime?

99.9% or higher. That allows about 44 minutes of downtime a month. Payments, healthcare and other critical systems aim for 99.99%. The average site in this report ran at 98.71%. So 99.9% already puts you ahead of most sites.

How is uptime calculated?

uptime % = (time online / total time) × 100. A site that was down for 44 minutes in a 30-day month had 99.9% uptime. Your number is only as good as your checks. Check every minute. Confirm each failure from a second location. Leave planned maintenance out.

Which uptime numbers should I track?

Four of them. Uptime, per month and over the last year. Time to fix: the median here is 1.9 minutes. The slow outages matter more than the median. Number of outages: the average site had 47. Outages outside business hours: 67.7% start then. Check who gets the alert at night.

Does Oh Dear alert on every failed check?

No. Half of all outages are over in under two minutes. So by default, we wait until a site has been down for two minutes before we alert you. You can change that per site.

Can I use these figures?

Yes. Quote any figure on this page, with a link to this page. All numbers are totals across all sites. Nothing here points to a customer, a domain or a site.

More answers in the full FAQ

Your own numbers

Hear about your next outage before your visitors do.

Oh Dear checks your site every minute, from two locations. You hear the moment it goes down. Every feature on. No credit card.

Capterra
4.9 (74) G2
4.7 (36)