Comparison

Sleep Time Calculator vs Time Calculator ×

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Sleep Time Calculator

This free utility helps you determine optimal wake-up times based on sleep cycles. It aims to reduce grogginess by recommending times to rise at the end of a sleep cycle, promoting a more alert feeling.

Highlights
  • Optimal wake-up time recommendations
  • Sleep cycle analysis
  • Reduces grogginess
  • Promotes alertness
  • Free to use
Features
Read full description

Know the best possible times to wake up with this free app. The five stages of sleep, including their repetition, occur cyclically. The first cycle, which ends after the completion of the first REM stage, usually lasts for 90 minutes. With 8 hours of sleep you typically go through 4-5 cycles a night. Waking up in the middle of a cycle leaves you feeling groggy, but waking up at the end of a cycle leaves you feeling awake and alert. This app gives you recommendations on when to wake up in the morning to decrease the likelihood that you will feel groggy.

About

Time Calculator ×

Effortlessly perform calculations with time values like addition, subtraction, multiplication, and division. Supports various time formats including days, hours, minutes, and seconds. Features a user-friendly interface for simple and functional time arithmetic.

Highlights
  • Time addition and subtraction
  • Time multiplication and division
  • Support for days, hours, minutes, seconds
  • Flexible time format input/display
  • User-friendly interface
Features
Read full description

Introducing the upgraded Time Calculator app – your ultimate tool for seamless time-based calculations! Time Arithmetic Made Easy: Perform mathematical operations with time values like addition, subtraction, multiplication, division and more. No more struggling with complex time conversions – let our app handle the math for you. Flexible Time Formats: Input and display time values in various formats, including days, hours, minutes, and seconds. Customize the format that suits your preference or matches your specific needs. User-Friendly Interface: Designed for both simplicity and functionality, modelled after the native iPhone calculator, our app ensures a smooth user experience, regardless of your familiarity with time-based calculations. You can perform calculations such as: 1h 45m + 3h 20m 2h 38m x 2 8h - 1h 11m 14h ÷ 4 Terms of Use: https://doubleuapp.com/privacy/terms.html

Screenshots

Sleep Time Calculator4 screens
Time Calculator ×4 screens

Verdict

The call

The clearest difference is rating: Time Calculator × at 4.7 against Sleep Time Calculator's 3.8. Time Calculator × also leads on ratings volume (288 vs 23). Sleep Time Calculator's advantage is in-app purchases (none vs 4) and ads (none vs shown). On price, review sentiment, update cadence and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Time Calculator × sells 4 in-app purchases, starting at $4.99 per year. Sleep Time Calculator asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Time Calculator × holds the better App Store score, 4.7 against 3.8. That said, the two scores are not equally well evidenced: Time Calculator × has 288 ratings behind it against 23, so its average is the more settled of the two. Written reviews point the same way: 70% of Sleep Time Calculator's written reviews are positive against 73% of Time Calculator ×'s.

UpkeepUpdate frequency

Sleep Time Calculator ships an update every 3 months, Time Calculator × every 6 months. Both last shipped on October 23, 2026.

Scorecard6 real differences · 4 level
Sleep Time Calculator versus Time Calculator ×: the parameters behind the verdict, then further details
ParameterSleep Time CalculatorTime Calculator ×
PriceFreeFree
Rating3.8 (23 ratings)4.7 (288 ratings) — better
Positive reviews69.7% of reviews73.1% of reviews — better
Number of ratings23288 — better
Update frequencyEvery 3 months — betterEvery 6 months
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS8.0 — better15.6
Further details — not scored
Size55 MB28 MB
Age rating12+4+
DeveloperRecked Software LLCDOUBLE U s.r.o.

Customer experience

Sleep Time Calculator

All ratings22 ratings
Positive68.2%
Neutral4.5%
Negative27.3%
Written reviews33 reviews
Positive69.7%
Neutral0.0%
Negative30.3%

Time Calculator ×

All ratings287 ratings
Positive92.0%
Neutral2.4%
Negative5.6%
Written reviews52 reviews
Positive73.1%
Neutral3.8%
Negative23.1%

Bugs and requests

Sleep Time Calculator

Not enough reviews yet to summarise bugs or requests.

Time Calculator ×

Reported bugs

4 issues
  • Paid subscription, but ads still appear
  • App defaults to D-H-M format, which is not preferred
  • Calculation error: 3:64 should be 4:04
  • Subtraction calculation error: 12:15pm from 6:45pm gives wrong answer

Requested features

2 requests
  • Make it pure hours and minutes, not days
  • Option to disable 'DAYS' format

In-app purchases

None

Sleep Time Calculator

No in-app purchases

4 purchases

Time Calculator ×

Subscriptions1
  • Premium Yearly$4.991 Year
One-time3
  • Remove Ads$6.99
  • Remove Ads$9.99
  • Remove Ads$19.99

Questions

Is Sleep Time Calculator free?
Sleep Time Calculator is free to download, with no in-app purchases.
Is Time Calculator × free?
Time Calculator × is free to download, with in-app purchases available.
Which has better reviews, Sleep Time Calculator or Time Calculator ×?
Time Calculator × is rated higher. Sleep Time Calculator averages 3.8 out of 5 from 23 ratings, while Time Calculator × averages 4.7 from 288 ratings.
Do Sleep Time Calculator or Time Calculator × have ads?
Time Calculator × shows ads; Sleep Time Calculator does not.
Which is updated more often, Sleep Time Calculator or Time Calculator ×?
Sleep Time Calculator ships an update every 3 months, and Time Calculator × every 6 months. Most recently, Sleep Time Calculator was updated on October 23, 2026 and Time Calculator × on October 23, 2026.

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