P Numbers vs SUN
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
P Numbers
Quickly access weldability grouping numbers for welding procedures and performance qualifications. This app provides data from authoritative sources like ASME Section IX and AWS B2.1.
- Base metal weldability grouping lookup
- Welding procedure qualification data
- Performance qualification data
- ASME Section IX Table QW/QB-422 data
- AWS B2.1 Table C1 and C2 data
- ISO/TR 20173 data
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P-Numbers: Quick lookup of base metal weldability grouping numbers for welding procedure and performance qualification. Data is provided by C-spec from the master source used for generation, proof-reading and maintenance of ASME Section IX Table QW/QB-422, AWS B2.1 Table C1 and C2, and ISO/TR 20173.
SUN
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The SUN-TEC Hardness Converter is a tool for converting data from one hardness scale to another scale(s) and measuring the hardness of Metallic materials for your applications. Features and Benefits: - Convert between Rockwell, Vickers, Knoop, Brinell, and Leeb hardness scales. - Minimum Thickness and Cylindrical corrections for Rockwell scales. - Diagonal Length(s) conversion to Hardness and Hardness to Diagonal Length(s) for Vickers, Knoop, and Brinell scales. Available Scales: - HRA - HRB - HRC - HRD - HRF - HR15N - HR30N - HR45N - HR15T - HR30T - HR45T - VICKERS - KNOOP - BRINELL - LEEB (HLD) Note: All information within this application tool is for reference only.
Screenshots
Verdict
The clearest difference is update cadence: SUN at every 14 months against P Numbers's every 39 months. P Numbers's advantage is device support. On price, in-app purchases and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
P Numbers ships an update every 39 months, SUN every 14 months. The most recent releases landed on October 2, 2026 and October 11, 2026 respectively.
| Parameter | P Numbers | SUN |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (5 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 5 — better | — |
| Update frequency | Every 39 months | Every 14 months — better |
| Ads | No | — |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod — better | — |
| Requires iOS | 13.0 — better | 13.4 |
| Further details — not scored | ||
| Size | 13 MB | 24 MB |
| Age rating | 4+ | 17+ |
| Developer | ASMEIX CORPORATION | SUN-TEC CORPORATION |
In-app purchases
P Numbers
No in-app purchases
SUN
No in-app purchases
