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Isotope Pattern Calculator v4.5

----- For all possible isotopes version -----

Developed by Junhua Yan 2001.9

Please type molecular formula (case sensitive):

[See help in detail] [If this software not work, please visit or]
Some sample of syntax for molecular formula:
1. CuSO4.5H2O; CH3(CH2)9COOH; PhOH; AcOEt (The Periodic Table shows the elements supported; The Symbols of Groups supported. #Add your Groups! )
2. Gly-Ile-Ala-Thr-Asp; GlyIleAlaThrAsp----   (The symbols of Amino Acid supported)
3. [14C]6[3H]5OH; C6H5[14C]6H4[18F]    ( [14C] presents 14C(isotope); [18F] presents 18F(isotope); It supports all possible isotopes. If you just want to calculate naturally occurring isotopes, please click here.)

With the natural abundance of isotopes    With customized abundance of isotopes (For some enriched isotopes)#

Low Resolution                            High Resolution
Show peaks from mass value to . (Optional)
Some mass peaks which relative abundances are
Set decimal places for the exact  mass in the data table = *
Set tags for all  peaks  = *
Set offset of the up-down position of  tags  = 

* (Increase this value, the tags will move down; Decrease this value,  the tags will move up.)  

Set offset of the left-right position of  tags  = 

* (Increase this value, the tags will move right; Decrease this value,  the tags will move left.)  


#: "Add your groups" and "Customizing Isotope Abundance" need set "Cookie" enable if you want to use these functions.
*: The items are just for high resolution.
1. if you want to calculate molecular weight online, please click here.
2. Molecular weight Calculator for Windows 9X, Windows Me, Windows NT, Windows 2000 and Windows XP, click here to download it.
3. If you can not print the calculated result, please click here for help.

If you have any questions or suggestions, please contact me. My email address is
This software is not free software, don't copy it to anyone else without my permission
2001.8 - 2001.9 All rights reserved