Free NDT Calculators & Tools

Calculate half-value and tenth-value layers for Ir-192, Co-60, and Se-75 gamma sources through lead, steel, and concrete. Per ANSI N43.3 shielding tables.

Calculate gamma radiography exposure time for Ir-192 on D4/D5/D7/D8 film classes using the exposure-factor method per ASTM E94 and ASME V Article 2.

Calculate radiographic geometric unsharpness from focal-spot size, source-to-object, and object-to-film distance. Check Ug against ASME V / ASTM E1742 limits.

Decay an industrial radiography source to its current activity using A(t) = A₀ × exp(-λt) with half-life values from ANSI N43.3.

Generate a Distance Amplitude Correction or Time-Corrected Gain curve from 3+ reference reflectors per ASME V Article 4 and ASTM E2192.

Size a planar UT indication using the 6 dB drop method per ASTM E2192 and ASME V Article 4. Returns through-scan defect length with beam-spread correction.

Calculate ultrasonic angle-beam skip distance and beam path for weld inspection — half-skip and full-skip surface distance and sound path from wall thickness and refracted angle.

Compute the refracted shear-wave angle in steel from a wedge incidence angle using Snell's Law. Verifies probe wedge selection per ASME V Art. 4.

Calculate ultrasonic attenuation loss for carbon steel, stainless, aluminum, copper, plastic, and concrete at 1–25 MHz. Separates material absorption from geometric spreading. Per EN 583-2.

Calculate ultrasonic near-field length, -6 dB and -20 dB half-angles, and beam width at depth. Steel, aluminum, copper, plastic. Per ASTM E317 and EN 12668-2.

Calculate Condition Monitoring Location (CML) count, grid spacing, and re-inspection interval for piping & vessel UT surveys. Per API 570, API 510, API 574 grid sizing rules.

Convert ultrasonic amplitude ratios to decibels and back. Compute dB difference between two signals and the gain needed to set a signal to 80% FSH.

Calculate ultrasonic near-field (Fresnel zone) length from probe diameter, frequency, and material velocity. Find where the beam focuses and is usable for flaw sizing.

Correct ultrasonic thickness readings for high-temperature surfaces. Sound velocity in steel falls ~1% per 55°C, so a gauge calibrated at ambient reads thick on hot equipment. Per ASME V and Olympus/Evident field practice.

Convert ultrasonic time-of-flight to wall thickness in mm and inches. Uses t = (v × Δt) / 2, the pulse-echo equation per ASTM E797 and API 510.

Calculate the eddy current fill factor for a bobbin probe in tube inspection — η = (coil diameter / tube ID)². Higher fill factor means better sensitivity. Per ASME V Article 8 / ASTM E690.

Compute eddy current test frequency from desired depth of penetration using δ = 1 / sqrt(π × f × μ × σ). Per ASTM E309 and ASNT recommended practice.

Calculate eddy current standard depth of penetration (skin depth) from material conductivity, permeability, and frequency. Pick the right EC test frequency.

Calculate magnetic particle coil ampere-turns and current for longitudinal magnetization per ASTM E1444 / E1444M — low-fill and high-fill (cable-wrap) formulas.

Compute applied magnetic field for MT inspection per ASTM E1444 §7. Solenoid coil amp-turns and field strength for yokes per ASME V Art. 7.

Look up correct penetrant and developer dwell times for liquid penetrant inspection per ASTM E165 §10.5 / E1417 Table 2 and ASME V Article 6.

Calculate long-term and short-term corrosion rate, remaining life, and the maximum inspection interval for pressure vessels, piping and tanks per API 510, API 570 and API 653.

Convert between Brinell (HB), Rockwell C (HRC), Rockwell B (HRB) and Vickers (HV) hardness, with approximate tensile strength, for steel. Based on ASTM E140 conversion tables.

Track NDT certification expiry and renewal windows: ASNT Level II/III (5-yr), AWS CWI (3+9 yr), API 510/570/653 (3-yr), PCN, ISO 9712. Required CE hours per cert.

Estimate NDT inspection cost by method, area, access, and travel. US market rates for UT, RT, MT, PT, PAUT, and TOFD as of 2025.

Calculate equipment remaining life and the next inspection interval from thickness and corrosion rate, applying the API half-life rule and code maximums (510, 570, 653).

Pick the right NDT method for the material, defect type, and access constraints. Logic follows ASNT recommended practice and API 510/570/653.

Estimate per-weld inspection cost by method (UT, RT, MT, PT, PAUT), pipe size, wall thickness, and access. Per-joint pricing benchmarks from US contractor rate cards.

Estimate deposited weld metal weight and filler-metal consumption for single-V butt and fillet welds. Cross-section × length × steel density ÷ deposition efficiency (SMAW, GMAW, FCAW, SAW).

Compute boundary distance for Ir-192, Co-60, and Se-75 sources using D = sqrt(A × Γ / dose-rate). Conforms to 10 CFR 20.1301 and ANSI N43.3.