Common signs: times off by hours, wrong dates near midnight, and bugs after daylight saving changes. Usual causes: mixed time zones and local-time storage. What we do: store UTC, convert correctly and add tests. What you get: correct dates for every user.
Our timezone and date bug fix corrects times that show hours off, dates that change near midnight, daily resets at the wrong moment and bugs that appear after daylight saving changes. A Codersarts engineer finds every place dates are handled, fixes them consistently and adds tests. Fixed price from $29 with 24h delivery.
Timezone & Date Bug Fix at a Glance
Item | Details |
|---|---|
Starting price | $29 for one bug |
Delivery | 24 hours |
Stacks | JavaScript and TypeScript, Python, Java, PHP, PostgreSQL, MySQL, MongoDB and Firebase |
Fixes | Wrong times, off-by-one dates, DST bugs, scheduling and daily resets |
Includes | Root-cause fix and tests across time zones |
What you get | Correct dates for every user |
Revisions | One revision round included |
Why Do Timezone Bugs Happen?
Timezone bugs happen when an app mixes the server's time zone, the user's time zone and stored values without clear rules. Common causes are storing local times instead of UTC, comparing dates without time zones, and assuming every day has 24 hours, which breaks during daylight saving changes.
Signs You Have Date Bugs
Times show several hours off for some users
Dates are one day early or late
Streaks, deadlines or daily bonuses reset at the wrong time
Bugs appear twice a year around daylight saving
Scheduled jobs run at the wrong hour
Common Causes
Local storage
Times saved without a time zone.
Server time
Logic based on the server's time zone.
String dates
Dates parsed from strings inconsistently.
DST
Days that are 23 or 25 hours long.
Quick Checks You Can Try First
Check what time zone your server and database use.
Look at how dates are stored: with or without time zones.
Test the app with a device set to another time zone.
Note when bugs started: near a DST change?
If the problem remains, our engineers take it from there.
How We Fix It
Reproduce. We reproduce the bug in several time zones.
Find all. We trace every place dates are created and compared.
Standardize. Store UTC and convert at display time.
Fix logic. Daily resets and deadlines use the user's time zone.
Test. Tests across time zones and DST changes.
Document. Simple date-handling rules for your team.
What You Get
The bug fixed at its root
Consistent UTC storage and conversion
Tests across time zones and DST
A list of other risky date code
Date-handling rules for your team
Example result (illustrative)
A coding platform's daily streaks reset at the wrong time for students outside India, and some lost streaks overnight. The check compared server dates in IST with user dates. We moved storage to UTC, calculated each user's day in their own time zone and added tests for several zones and DST changes. Streak complaints stopped.
What Is Included and Not Included
Included | Not included |
|---|---|
One reported bug and related code | Rewriting unrelated features |
Tests across time zones | Data migration for very large tables |
Date-handling rules | Ongoing support |
One revision round | New features |
Pricing for Date Bug Fixes
Package | Best for | Starting at | Delivery |
|---|---|---|---|
Single bug fix | One date or time bug | $29 | 24 hours |
Date handling cleanup | All date logic standardized with tests | $199 | 1 day |
Data correction | Fix stored dates plus logic | $599 | 3 days |
You get a fixed quote after we review your setup. You approve the scope before any payment.
Who This Is For
Apps with users in several countries
Booking, scheduling and calendar apps
Learning apps with streaks and deadlines
Apps with daily resets or reports
What We Need From You
Repository access
Steps to reproduce
Server and database time zone
Example affected users
Code and data privacy
We sign an NDA on request, work with the least access needed, and never keep copies of your data after delivery. You own all code, configuration and notes.
Key Terms Explained
UTC: Coordinated Universal Time, the standard reference time
DST: daylight saving time
IANA time zone: a named zone such as Asia/Kolkata
Off-by-one: a date one day early or late
Common Mistakes We Avoid
Storing local times
Using fixed offsets instead of named time zones
Testing only in your own time zone
Assuming every day has 24 hours
Need More Than One Task?
Seeing many bugs at once? See Regression Testing. Or use Prepaid Developer Hours to cover several tasks from one prepaid balance.
Related Tasks
Gamification Logic Fix for streaks and daily bonuses
Add Unit Tests to Your Code to prevent regressions
Functional QA Test Pass to find other bugs
Frequently Asked Questions
Why are dates off by one day?
Usually because a date is created in UTC and shown in a local time zone, or the reverse.
Should we store dates in UTC?
Yes, store timestamps in UTC and convert to the user's time zone when displaying or calculating days.
Which libraries do you use?
Native Intl and Temporal, date-fns-tz or Luxon in JavaScript, and zoneinfo in Python.
Can you fix wrong data already saved?
Yes, as a data correction task.
Show the Right Time to Every User
Share the bug and your stack, and a Codersarts engineer will fix it within a day.