Math & Numbers

Calculate engineering stress σ = F/A and engineering strain ε = ΔL/L₀ under uniaxial load. Choose what to solve: for stress, enter force F (N) and cross-section area A (mm²) → result in MPa; for strain, enter original length L₀ and elongation ΔL (negative for compression) → dimensionless ratio. Units are self-consistent (N, mm) so stress comes out directly in MPa.

Security

Show each HMAC step of HKDF Extract+Expand for protocol key derivation, including PRK, T(n), and OKM.

Math & Numbers

Calculate the infinite-slope factor of safety: FS = c'/(γ·z·cosβ·sinβ) + tanφ'/tanβ. Supports dry slopes and seepage parallel to the slope. Returns FS and a stable/marginal/unstable classification.

Media

Edit subtitle timing, shift cues, repair overlaps, calibrate CPS, wrap long lines, and export SRT, VTT, ASS, or TTML.

Math & Numbers

Calculate the maximum bending moment M_max, maximum shear force V_max and support reactions for a simply supported beam under a uniformly distributed load, a mid-span point load, or a point load at an arbitrary position. UDL: M_max = qL²/8; mid-span: M_max = PL/4; offset: M_max = P·a·b/L.

Math & Numbers

Calculate the elastic potential energy and force of a spring in compression or extension. U = ½·k·x², F = k·x. Solve energy from displacement, or displacement from energy.

Math & Numbers

Calculate the stiffness (spring rate) of a cylindrical helical compression/extension spring. k = G·d⁴ / (8·D³·n) in N/mm. Includes shear-modulus presets for common spring materials.

Media

Reduce broadband noise with a spectral filter chain

Health

Find the best bedtime or wake time based on the brains 90-minute sleep-cycle rhythm. Enter a target wake time and get recommended bedtimes, or enter a bedtime to project forward.

Media

Stream-copy trimming.

Media

Readable stream and codec report for media files.

Media

Rewrap media containers with stream copy.