I lost all my contacts while fomatting my samsung how can i get them back

You can try GT Recovery for Windows.
Accidently deleted some contacts on your Samsung Galaxy S6 ? A software can help you from big headache of Restoring deleted Contacts.
Here on video we Show you step-by-step guide to recover deleted contacts on android device with GT Recovery for Windows.
With this way you can recover deleted contacts on any brands of Android device such as Samsung, HTC, Huawei, Sony, Motorola, Lenovo, LG, Sharp, etc.
Twitter:https://twitter.com/GtRecoveryapp
Facebook Homepage:https://www.facebook.com/GT-Recovery-for-Windows-527139864132104/

Are you using an iPhone, Michelle? If so, here's a guide to help you even if you don't have backup.
How to Recover Deleted Contacts from iPhone without Backup

Accidently deleted some contacts on your Android ? A software can help you from big headache of Restoring deleted Contacts.
Here on video we Show you step-by-step guide to recover deleted contacts on android device with GT Recovery for Windows.
With this way you can recover deleted contacts on any brands of Android device such as Samsung, HTC, Huawei, Sony, Motorola, Lenovo, LG, Sharp, etc.

I deleted all of my contacts by mistake,can you help me get them back?

Firstly, you should make sure that do you have maken a backup before.
You can find the backup of contacts in the following place:

1. google account, if you have a google account and open the sync, the account might make a backup for your phone before, thus,when you lost your contacts, you can recover them from google account.

2.Official PC companion in computer, generally, you should upgrade the android phone via official PC companion provided by manufacturer, and this PC companion will make a backup for the phone when you connect the phone to the computer,and lauch the application,if you have open the automatical backup fuction.

3.3rd-party android phone assistant, I think you might have installed a 3rd-party android phone assistant for installing apps conveniently, and most of android phone assistant have a backup feature as PC companion.

so, you should try the ways above to recover contacts.

However, if you do not have any backup, and you have a vcf files in the phone'SD card, I think you can recover the vcf files from the SD card. learn more here: Android Data Recovery

I have had success with this photo recovery program... Download the program from
http://download.cnet.com/Asoftech-Photo-Recovery/3000-12511_4-10913438.html?part=dl-10913438&subj=dl&tag=button

You have to use a card reader either on your computer or an external USB card reader. Put the card in the card reader, open the recovery program, then select the drive where files are deleted, then press "Start" and wait for it to do it's magic.

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