# LED Calc. vs Timer 555 Calculator

The clearest difference is review sentiment: Timer 555 Calculator at 100% against LED Calc.'s 50%. Timer 555 Calculator also leads on rating (3.9 vs 1.0) and ads (none vs shown). LED Calc.'s advantage is in-app purchases (none vs 1). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Timer 555 Calculator sells 1 one-off in-app purchase. LED Calc. asks for nothing beyond the download.

Timer 555 Calculator holds the better App Store score, 3.9 against 1.0. That said, the two scores are not equally well evidenced: Timer 555 Calculator has 8 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 50% of LED Calc.'s written reviews are positive against 100% of Timer 555 Calculator's.

LED Calc. ships an update every 10 months, Timer 555 Calculator every 3 months. The most recent releases landed on June 5, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | LED Calc. | Timer 555 Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/led-calc/id556845805/reviews) | **[3.9 (8 ratings)](https://appshunter.io/ios/app/timer-555-calculator/id834044557/reviews)** |
| Number of ratings | 1 | **8** |
| Positive reviews | 50.0% of reviews | **100.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 10 months | **Every 3 months** |
| Monetization | **Ad-supported** | Free with in-app purchases |
| Size | 17 MB | 3 MB |
| Requires iOS | **12.0** | 13.2 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Jibiki Works](https://appshunter.io/developer/556845808) | [Siu Yuen Ho](https://appshunter.io/developer/814088527) |

## What reviewers say

### LED Calc.

[App page](https://appshunter.io/ios/app/led-calc/id556845805)

This application assists in designing electronic circuits by calculating the necessary resistor values for LEDs. It simplifies the process of determining the correct components for your LED projects.

**Highlights:** Resistor value calculation, LED circuit design assistance, Component value determination

**Features:** macOS Compatibility

**In-app purchases:** none


### Timer 555 Calculator

[App page](https://appshunter.io/ios/app/timer-555-calculator/id834044557)

Calculate monostable and astable circuits for electronics projects. Determine pulse width and frequency, find component combinations, and save/upload data. Supports multiple languages.

**Highlights:** Monostable circuit pulse width calculation, Astable circuit frequency calculation, Component combination finder, Save component values to CSV, Upload CSV via AirDrop/iCloud Drive, Multi-language support

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Pro feature | $0.99 | one-time |


## Frequently asked questions

### Is LED Calc. free?

LED Calc. is free to download, with no in-app purchases.

### Is Timer 555 Calculator free?

Timer 555 Calculator is free to download, with in-app purchases available.

### Which has better reviews, LED Calc. or Timer 555 Calculator?

Timer 555 Calculator is rated higher. LED Calc. averages 1.0 out of 5 from 1 ratings, while Timer 555 Calculator averages 3.9 from 8 ratings.

### Do LED Calc. or Timer 555 Calculator have ads?

LED Calc. shows ads; Timer 555 Calculator does not.

### Which is updated more often, LED Calc. or Timer 555 Calculator?

LED Calc. ships an update every 10 months, and Timer 555 Calculator every 3 months. Most recently, LED Calc. was updated on June 5, 2026 and Timer 555 Calculator on September 24, 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.*