# TDF Calc — Time Dose Fractionation > Radiation therapy dose fractionation calculator using the linear-quadratic model. (iPhone/iPad app by Eye Physics.) - Source: https://appshunter.io/ios/app/tdf-calc/id312749340 (this page in markdown: same URL + `.md`) - Developer: [Eye Physics](https://appshunter.io/developer/312749343) - Category: Medical, Education - Price: Free - Rating: 5.00/5 from 1 App Store ratings · 1 written reviews indexed - Age rating: 4+ - Requires: iOS 13.2 · 2 MB - Languages: American English - Released: 2009-05-05 - Data updated: 2026-06-05 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/tdf-calc/id312749340/reviews.md ## What is TDF Calc? TDFCalc is an application which implements the linear-quadratic (LQ) method for comparing the biologically effective dose (BED) of external beam radiation therapy (EBRT) fractionation regimens as well as low dose rate (LDR) and permanent implant brachytherapy treatments. It calculates BED for a given alpha/beta ratio as a function of the dose per fraction and number of fractions for EBRT, and initial dose rate for brachytherapy. For a predetermined BED, the app solves the quadratic equation to calculate dose per fraction as a function of the number of fractions desired. This enables quick comparison of modified fractionation regimens (e.g. hypofractionation or compensating for missing treatment fractions) vs a conventional and/or originally intended regimen. ## Key features - Linear-quadratic (LQ) method implementation - Biologically effective dose (BED) calculation - External beam radiation therapy (EBRT) fractionation - Low dose rate (LDR) brachytherapy - Permanent implant brachytherapy - Dose per fraction calculation ## Recent user reviews (1 of 1) All indexed reviews: https://appshunter.io/ios/app/tdf-calc/id312749340/reviews.md ### 4/5 — Very nice very simple application for getting BED calculations. *2009-12-22* This app can be thought of as a light version of the "TDF Plan" software available for desktops. This is a good first version application, but it may be priced too highly at 9.99 without adding additional features. Despite inheriting the TDFCalc name the application only calculates BED's. BED is the new standard, however it is often useful to compare BED results with TDF results when discussing the matter with a college. I would also love it if this application could email a simple report of the calculation. It would be nice to add support for additional features such as: 1. In ESC calculator: ability to specify dose for new regimen and see closest #fractions needed 2. Button to turn on TDF comparison (ex. BED ESC 17fx at 250cGy, TDF = X fx at 250cGy). 3. Support for multiple courses of treatment (i.e. save regimen as course). 4. HDR, CyberKnife settings 5. Landscape view for viewing multiple courses and results of ESC calculator all on one screen. ## Frequently asked questions about TDF Calc ### What is TDF Calc used for? TDF Calc implements the linear-quadratic (LQ) method to calculate the biologically effective dose (BED) for radiation therapy fractionation regimens. It helps compare different treatment schedules and determine optimal dose per fraction. ### What types of radiation therapy does TDF Calc support? TDF Calc supports external beam radiation therapy (EBRT) fractionation, as well as low dose rate (LDR) and permanent implant brachytherapy treatments. ### Can TDF Calc help compare different fractionation schedules? Yes, TDF Calc enables quick comparison of modified fractionation regimens, such as hypofractionation or compensating for missing treatment fractions, against conventional or originally intended regimens. ### What is the alpha/beta ratio used for in TDF Calc? The app calculates BED for a given alpha/beta ratio, which is a key parameter in the linear-quadratic model used to predict the biological effect of radiation. ### What devices is TDF Calc available on? TDF Calc is available for iPhone and iPod devices. ### How often is TDF Calc updated? The latest version of TDF Calc is 2.0.0, and it was last updated on May 31, 2020. Users can expect updates to maintain compatibility and potentially add new features. ### What is the age rating for TDF Calc? TDF Calc has an age rating of 4+, making it suitable for a wide range of users. ### Does TDF Calc have ads? No, TDF Calc does not contain advertisements, providing an uninterrupted user experience. ## Version history (last 3 releases) ### 2.0.0 — 2020-05-31 Completely rewritten for recent iOS versions. Now Includes: - LDR and permanent brachytherapy modes as well as external beam. - Integrated access to the user guide. - Landscape view support. - Email calculations to yourself or others. - Configuration settings for radiobiological and brachytherapy parameters. - Equivalent Single Course "reverse" calculator. ### 1.0.4 — 2009-05-12 1. User interface and general appearance tweaks. 2. More detailed instructions for use. ### 1.00 — 2009-05-05 No release notes. ## Apps similar to TDF Calc | App | Rating | Price | Category | | --- | --- | --- | --- | | [ICCR](https://appshunter.io/ios/app/iccr/id717358930) | 5.0 (2) | Free | Medical | | [Manual of Clinical Oncology](https://appshunter.io/ios/app/manual-of-clinical-oncology/id883379133) | 4.5 (18) | Free | Medical | | [ESTRO 2026](https://appshunter.io/ios/app/estro-2026/id1614477899) | — | Free | Medical | | [Spine Physics](https://appshunter.io/ios/app/spine-physics/id1566693028) | 5.0 (1) | Free | Medical | | [GadCalc](https://appshunter.io/ios/app/gadcalc/id1051070769) | 5.0 (2) | Free | Medical | | [Radiation Oncology: Review](https://appshunter.io/ios/app/radiation-oncology-review/id6483211494) | — | Free | Medical | ## Related topics [tdf calc](https://appshunter.io/ios/topics/tdf-calc) · [tdf calculator](https://appshunter.io/ios/topics/tdf-calculator) · [dose calculator radiation](https://appshunter.io/ios/topics/dose-calculator-radiation) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-05.*