# Radisize vs Markday

The clearest difference is update cadence: Markday at every 3 weeks against Radisize's every 5 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Radisize sells 1 one-off in-app purchase and Markday sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Radisize ships an update every 5 months, Markday every 3 weeks. The most recent releases landed on November 1, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Radisize | Markday |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | Free | — |
| Size | 56 MB | 14 MB |
| Requires iOS | 18.0 | **17.0** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Zippy IT Solutions Ltd.](https://appshunter.io/developer/1841666879) | [Pinkod IT Solutions Ltd.](https://appshunter.io/developer/1884734546) |

## What reviewers say

### Radisize

[App page](https://appshunter.io/ios/app/radisize-radiator-calculator/id6755719529)

Calculate the precise radiator output needed for any room based on its dimensions, glazing, and materials. Generate professional PDF reports for planning and documentation. All calculations are performed offline on your device.

**Highlights:** Room-by-room radiator sizing, Multiple property management, Guided room setup wizard, Accurate BTU and kW outputs, Customizable settings (units, ΔT), Professional PDF report export, Offline-first operation

**Features:** macOS Compatibility, Family Sharing, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Radisize Pro | $2.99 | one-time |


### Markday

[App page](https://appshunter.io/ios/app/markday-countdown-and-widget/id6764439710)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Markday Pro — Lifetime | $3.99 | one-time |


## Frequently asked questions

### Is Radisize free?

Radisize is free to download, with in-app purchases available.

### Is Markday free?

Markday is free to download, with in-app purchases available.

### Do Radisize or Markday have ads?

Neither Radisize nor Markday shows ads.

### Which is updated more often, Radisize or Markday?

Radisize ships an update every 5 months, and Markday every 3 weeks. Most recently, Radisize was updated on November 1, 2026 and Markday on October 31, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*