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LabJ - Electronic Laboratory Notebook, ELN
[Laboratory Journal for Organic Chemistry Laboratories v. 2.x]


LabJ Window LabJ (a.k.a Electronic Laboratory Notebook, ELN, Laboratory Journal) assists in planning chemical reactions and stores chemical information. It calculates information such as molecular weights, moles, reactant amounts and volumes, percent yields and more. Notes (pocedures, results, references, comments, graphics, etc.) can be attached to the LabJ records. LabJ can be also used to store various data of synthetizing compounds, such as melting and boiling points, spectral data as well as unlimited number of custom fields for your specific needs.

LabJ is realized as an database file for MDL ISIS/BaseTM program. *) Reaction drawings and (sub)structure searches use the ISIS/DrawTM module. *)

Following is a brief overview of the most prominent features of LabJ:

LabJ is a calculations and database program for organic chemists. Chemical reactions can be easily introduced by drawing them in ISIS/Draw module.

LabJ eliminates most of the tedious work of calculating chemical reaction data such as molecular formulas and weights of reactants and products, amounts and volumes of the reactants and yields of products. Calculations are based on graphical reaction and choosed scale, stoichiometry and purity of reagents. Reactants volumes are calculated based on either reagents density or molarity (M [mol/L]).

Because LabJ uses ISIS/Base program as an "database engine" all records can be easily stored and searched. If you want to re-egzamine or scale-up a reaction simply retrieve an existing record, duplicate it, change one of more values (incl. reagents), and everything is recalculated.

All records in a LabJ database are sequenced in numeric order based on reaction number (e.g. KG-1023). Simillary, all products (and fractions) can be logically labelled based on reaction number (e.g. KG-1023-1-3). You can browse throught the database page by page or search for a record by reaction number, reaction scheme, (sub)structure, analytical data, procedure, keywords and much more. This saerch tool generates a list that can be browsed, printed (as separated pages or in tabular form) or saved as a new LabJ database. Labj on Mac

LabJ prints records in a form of Reaction Page, Report Page, Tabular Form, and various Analytical Forms (e.g. for IR, MS departments), as well as virtually unlimited number of custom forms for your specific needs. Click here to download a copy of printed record: forms.pdf (Adobe Acrobat PDF file, 140KB).


{New} Current version is: 2.3.4

  1. 2.3.4: Added separate package with LabJ for Macintosh and with LabJ-sources. Some minor form improvements.
  2. 2.3.0: User's Manual (22 pages).
  3. 2.3.0: Additional forms for data input, browsing and printing.
  4. 2.3.0: Incl. the "Compounds" database, created by Mr. David ElTom ( from the Max-Planck-Institut für Kohlenforschung. This database (German version) can be used with LabJ to manage properties of synthesized products.
  5. 2.3.0: Improved spreadsheet for stoichiometry calculations.
  6. 2.3.0: LabJ now calculates volumes of reagents using density or molarity.
  7. 2.3.0: LabJ now calculates excess of reagents (also based on reagent volume).
  8. 2.3.0: Some minor improvements.


The ISISTM/Desktop (ISIS/Base nad ISIS/Draw) software package. Please contact MDL Information Systems, Inc. for more information. *)

Currently, you can use LabJ with MDL ISIS/Base 2.x for Microsoft Windows and Apple Macintosh. It is also possible to use LabJ under Unix/Linux with Macintosh or Microsoft Windows emulators, such as Basilisk II, Win4Lin or WINE.


The LabJ is usable for the "chemistry community" free of charge by anybody for any commercial, non-commercial or purely in-house purpose, but it is not yet true GNU GPL program. *) Nevertheless you may adapt the functionality of the program to your local needs and redistribute copies of the package. If you add a valuable feature, or hunt down a bug, you are welcome to contact the author by email and the fix or feature will be most certainly integrated into the official release of LabJ.

However the LabJ package cannot be distributed as part of another program package. Particularly the author strictly forbid the MDL Information Systems, Inc. and its affiliated companies to include the LabJ package as a part of any product. If anybody is interested in providing the LabJ as integrated part of another package, this must be negotiated.

The author assumes no responsibility for errors or malfunctions, or for damages resulting from the use of the programs.

*) LabJ requires use of proprietary software programs ISIS(tm)/Draw and ISIS(tm)/Base from MDL Information Systems, Inc. ("MDL"), which are available under the appropriate licensing agreements from MDL from . MDL and its affiliated companies are in no way associated with, nor do any of them endorse LabJ, nor does your use of ISIS/Draw and/or ISIS/Base imply any such association or endorsement. Linux is a registered trademark of Linus Torvalds; MDL is a registered trademark in the United States, and ISIS is a trademark of MDL Information Systems, Inc.; ISIS/Draw and ISIS/Base are (c) MDL Information Systems, Inc. All Rights Reserved.


LabJ was originally writen for my own use and a lot of it is messy, so ideas on how to clean it up would be great (cf. Copyright). Please send bug descriptions, suggestions, new LabJ files or succesful stories to



{sit} Get labj2x.sit LabJ 2.x for Apple Macintosh, 56 KB {New}(requires ISIS/Base 2.x from MDL). Incl. the "Compounds" database.

{zip} Get LabJ 2.x for MS Windows, 65 KB d(requires ISIS/Base 2.x from MDL). Incl. the "Compounds" database.

{zip} Get LabJ 2.x definition files (sources) 98 KB {New}

{pdf}Download a copy of User's Manual: manual.pdf (Adobe Acrobat PDF file, 320KB).{New}

{pdf}Download a copy of sample records: forms.pdf (Adobe Acrobat PDF file, 140KB).{New}



    Apple Macintosh Users
  1. Get labj2x.sit file, which is a compressed Mac file.
  2. Use Stuffit (or similar application) to extract the archive.
  3. Double-click on the "labj" file to open it in the ISIS/BaseTM for Macintosh.
    MS Windows Users
  1. Get
  2. Use unzip *.zip command (DOS) to extract the archive. Alternatively you can use any GUI program, like WinZip (Windows) to extract the archive file
  3. Start ISIS/BaseTM and open the "labj.db" file

{Image - LabJ Logo}Karol (Charles) Grela

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Last updated Tuesday, 16-Sep-2008 23:27:43 CEST
(c) 1997-2023 Karol Grela (