An open source radiocarbon (14C) calibration software. Written in Python
Go to file
Stefano Costa 38356e8b33
ci/woodpecker/push/woodpecker Pipeline was successful Details
Merge pull request 'docs: more research papers and projects' (#55) from more-literature into main
Reviewed-on: #55
2023-10-30 13:44:10 +00:00
docs docs: more research papers and projects 2023-10-30 14:28:52 +01:00
iosacal maint: run black 23.10.0 on Python source files 2023-10-21 18:27:26 +02:00
tests maint: run black 23.10.0 on Python source files 2023-10-21 18:27:26 +02:00
.gitignore VS Code .gitignore 2022-01-07 11:13:45 -05:00
.pre-commit-config.yaml maint: fix #49 version mismatch of black between tox config and pre-commit config 2023-10-21 18:26:01 +02:00
.readthedocs.yaml docs: downgrade os and python version, fix #37 2022-08-29 14:58:03 +02:00
.woodpecker.yml maint: add Python 3.11 and 3.12 as CI targets 2023-10-24 14:29:25 +02:00 Update Code of Conduct to Contributor Covenant 2.1 2023-10-21 16:36:04 +00:00
LICENSE Add GNU GPLv3 license statement and file. 2008-12-09 08:50:27 +01:00 Add a file to include *.14c files in the distribution 2021-08-01 09:30:49 +02:00 docs: update README and remove reference to web app 2022-10-01 17:44:41 +02:00
pyproject.toml maint: fix #49 version mismatch of black between tox config and pre-commit config 2023-10-21 18:26:01 +02:00
setup.cfg maint: add setuptools as dependency 2023-10-24 23:02:25 +02:00

A radiocarbon calibration software

Codeberg CI DOI Documentation Status

IOSACal is the open source radiocarbon calibration software of the IOSA project. IOSACal includes a simple command-line program but it's best used as a toolkit in interactive and literate programming.

IOSACal is written in the Python programming language and it can run natively on any platform where the Python interpreter is available, including all Linux distributions, MacOS X and other UNIX operating systems, and Microsoft Windows.

Source code is made available under the terms of the GNU General Public License.

The documentation is online at thanks to Read the Docs.


Why another 14C calibration software ?

Most available programs for radiocarbon calibration, like OxCal, CALIB and others, are freeware. You don't have to pay for them, but on the other side you're not free to modify them as you need, nor to access and study the source code.

This is the main motivation behind IOSACal: creating a free-as-in-freedom radiocarbon calibration software, with a clean programming library, that enables experiments and integration in existing archaeological information systems.

Furthermore, writing this software from scratch is an alternative way of learning how 14C calibration works, not only in strict mathematical terms, but also from a practical point of view.


IOSACal takes a radiocarbon determination and outputs a calibrated age as a set of probability intervals. A radiocarbon date is represented by a date in years BP (before present, that is before 1950 AD) and a standard deviation, like 2430±170. The combination of these two values is a numerical representation of a laboratory measure performed on the original organic material.

The main task of the calibration process is to convert this measure into a set of calendar dates by means of a calibration curve. Users can choose whether they want results as a plot, a short textual summary or both (the plot includes the summary).

IOSACal reads calibration curves in the common .14c format used also by other programs. Should you have calibration data in another format, it would be easy to either convert them to that format or modify the source code of IOSACal to adapt it to your needs.

IOSACal is based on current calibration methods, like those described in the 2008 paper by C. Bronk Ramsey, Radiocarbon dating: revolutions in understanding, Archaeometry 50,2 (2008) pp. 249275

Can I use IOSACal for my research?

Yes, IOSACal has been used in research projects with large numbers of radiocarbon dates like Antarctica Marine Radiocarbon and the IPHES PALEODEM project.

Using IOSACal with Jupyter Notebooks is ideal for reproducible research that can be easily shared.

Furthermore, it takes little effort to customize and adapt the existing code to your specific needs.

IOSACal is reasonably fast, especially for batch processing.

If you make use of IOSACal in your work, please cite it with the IOSACal Zenodo DOI record:

This helps us get some recognition for creating and maintaining this software free for everyone.