Comparison

ISO Fits vs GD&T

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

ISO Fits

Calculate ISO fits and tolerances for shafts and bores. Supports metric and inch units, displays detailed fit definitions, and includes visual charts and educational videos.

Highlights
  • ISO fits calculation
  • Tolerance class display
  • Metric/inch unit switching
  • Tolerance charts
  • Updated YouTube videos
Features
Read full description

It includes the following features: - Fits calculation: Upon entering the nominal diameter (of either bore or shaft), users select their tolerance classes for bore and shaft. The app then provides the complete ISO fits definition with all relevant values. - Tolerances: Shows the tolerances for the most commonly used ISO tolerance classes. - switch between metric and inch version. - Charts: Shows the most common ISO tolerances classes in a diagram. - Videos: Features the automatically updated latest TSS youtube videos. The results of this application are based on DIN ISO 286 Nominal dimension: 1-3150mm following tolerances included: Shaft: a9, a10, a11, a12, a13, b8, b9, b10, b11, b12, b13, c8, c9, c10, c11, c12, cd5, cd6, cd7, cd8, cd9, cd10, d5, d6, d7, d8, d9, d10, d11, d12, d13, e5, e6, e7, e8, e9, e10, ef3, ef4, ef5, ef6, ef7, ef8, ef9, ef10, f3, f4, f5, f6, f7, f8, f9, f10, fg3, fg4, fg5, fg6, fg7, fg8, fg9, fg10, g3, g4, g5, g6, g7, g8, g9, g10, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11, h12, h13, h14, h15, h16, h17, h18, js1, js2, js3, js4, js5, js6, js7, js8, js9, js10, js11, js12, js13, js14, js15, js16, js17, js18, j5, j6, j7, j8, k3, k4, k5, k6, k7, k8, k9, k10, k11, k12, k13, m3, m4, m5, m6, m7, m8, m9, n3, n4, n5, n6, n7, n8, n9, p3, p4, p5, p6, p7, p8, p9, p10, r3, r4, r5, r6, r7, r8, r9, r10, s3, s4, s5, s6, s7, s8, s9, s10, t5, t6, t7, t8, u5, u6, u7, u8, u9, v5, v6, v7, v8, x5, x6, x7, x8, x9, x10, y6, y7, y8, y9, y10, z6, z7, z8, z9, z10, z11, za6, za7, za8, za9, za10, za11, zb7, zb8, zb9, zb10, zb11, zc7, zc8, zc9, zc10, zc11 Bore: A9, A10, A11, A12, A13, B8, B9, B10, B11, B12, B13, C8, C9, C10, C11, C12, C13, CD6, CD7, CD8, CD9, CD10, D6, D7, D8, D9, D10, D11, D12, D13, E5, E6, E7, E8, E9, E10, EF3, EF4, EF5, EF6, EF7, EF8, EF9, EF10, F3, F4, F5, F6, F7, F8, F9, F10, FG3, FG4, FG5, FG6, FG7, FG8, FG9, FG10, G3, G4, G5, G6, G7, G8, G9, G10, H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16, H17, H18, JS1, JS2, JS3, JS4, JS5, JS6, JS7, JS8, JS9, JS10, JS11, JS12, JS13, JS14, JS15, JS16, JS17, JS18, J6, J7, J8, J9, K3, K4, K5, K6, K7, K8, K9, K10, M3, M4, M5, M6, M7, M8, M9, M10, N3, N4, N5, N6, N7, N8, N9, N10, N11, P3, P4, P5, P6, P7, P8, P9, P10, R3, R4, R5, R6, R7, R8, R9, R10, S3, S4, S5, S6, S7, S8, S9, S10, T5, T6, T7, T8, U5, U6, U7, U8, U9, U10, V5, V6, V7, V8, X5, X6, X7, X8, X9, X10, Y6, Y7, Y8, Y9, Y10, Z6, Z7, Z8, Z9, Z10, Z11, ZA6, ZA7, ZA8, ZA9, ZA10, ZA11, ZB7, ZB8, ZB9, ZB10, ZB11, ZC7, ZC8, ZC9, ZC10, ZC11

About

GD&T

Read full description

Learn, interpret and inspect GD&T according to ISO 1101. This app describes a large range of definitions of geometric dimensioning and tolerancing and supports engineers and employees as a multimedia reference book. As part of operative education, this app shows relationships and makes it easier to understand the right handling of form and position tolerances in practice. This app explains the most important definitions of GD&T and its interpretation by examples (straightness, roundness, flatness, cylindricity, profile of a line, parallelism, squareness, angularity, position, concentricity, symmetry, circular runout, …) -25 animations -Basic information -Form tolerance -Profile tolerance -Position tolerance -Orientation tolerance -Runout tolerance

Screenshots

ISO Fits4 screens
GD&T4 screens

Verdict

The call

The clearest difference is in-app purchases: GD&T at none against ISO Fits's 1. ISO Fits's advantage is update cadence (every 5 months vs every 11 months). On price, ads, device support 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. ISO Fits sells 1 one-off in-app purchase. GD&T asks for nothing beyond the download.

UpkeepUpdate frequency

ISO Fits ships an update every 5 months, GD&T every 11 months. The most recent releases landed on November 6, 2026 and October 26, 2026 respectively.

Scorecard2 real differences · 8 level
ISO Fits versus GD&T: the parameters behind the verdict, then further details
ParameterISO FitsGD&T
PriceFreeFree
Rating4.2 (6 ratings) — better—
Positive reviews94.6% of reviews—
Number of ratings6 — better—
Update frequencyEvery 5 months — betterEvery 11 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.615.0 — better
Further details — not scored
Size66 MB56 MB
Age rating4+4+
DeveloperTrelleborg Sealing SolutionsCarl Zeiss AG

In-app purchases

1 purchases

ISO Fits

One-time1
  • Full Version with complete ISO286 Standard$1.99
None

GD&T

No in-app purchases

Questions

Is ISO Fits free?
ISO Fits is free to download, with in-app purchases available.
Is GD&T free?
GD&T is free to download, with no in-app purchases.
Do ISO Fits or GD&T have ads?
Neither ISO Fits nor GD&T shows ads.
Which is updated more often, ISO Fits or GD&T?
ISO Fits ships an update every 5 months, and GD&T every 11 months. Most recently, ISO Fits was updated on November 6, 2026 and GD&T on October 26, 2026.

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