The most powerful tangent line calculator for circles — built for students, engineers, and geometry enthusiasts. TangentCalc solves every type of tangent line problem instantly, with a live interactive graph and full step-by-step solutions. Whether you're solving analytic geometry homework, checking exam answers, or exploring coordinate geometry, TangentCalc gives you precise results in seconds. * THREE POWERFUL CALCULATION MODES External Point Tangents Enter any external point and circle — TangentCalc instantly computes both tangent points, both tangent line equations, the exact distance from point to center, and the tangent length. Every step is explained clearly so you can learn, not just copy answers. Tangent Lines by Slope Input any slope value and circle, and get the two parallel tangent lines that touch the circle at that angle. Perfect for analytic geometry problems where the line direction is given instead of a point. Tangent at a Point on the Circle Already know where the tangent touches the circle? Enter the point and get the exact tangent line equation immediately. Includes a smart "Snap to Circle" button that auto-projects any nearby point onto the circle for you. * LIVE INTERACTIVE GRAPH See your geometry come to life with a real-time visualization canvas: Pinch to zoom in and out freely Drag to pan across the coordinate plane Graph updates live as you type new values Tangent lines, tangent points, radii, and external points all displayed with color-coded clarity Resizable graph panel to suit your screen * STEP-BY-STEP SOLUTIONS TangentCalc doesn't just give you answers — it teaches you the math. Every calculation comes with a full, collapsible step-by-step solution showing: Distance formulas Tangent length derivation Tangent point coordinates Line equation construction Circle-form tangent formula Ideal for checking your own working or understanding how each result was reached. * CARTESIAN & POLAR COORDINATE SUPPORT Switch seamlessly between Cartesian (x, y) and Polar (r, θ) coordinate input. Toggle between Degrees and Radians for angular values. Cartesian equivalents are shown in real time when using polar mode so there's no confusion. * BUILT FOR ACCURACY All results are computed to 6 decimal places of precision. Equations are displayed in both slope-intercept form (y = mx + b) and general form (ax + by + c = 0). Selectable result text lets you copy values directly into your notes or assignments. * PERFECT FOR: High school and university geometry students Analytic geometry and calculus coursework Engineering and physics problem sets Teachers demonstrating tangent line concepts Anyone who needs fast, accurate circle-tangent calculations * DESIGNED FOR iOS Clean dark interface designed for focus. Monospaced math typography for clarity. Works on iPhone and iPad. No ads. No subscriptions. One download, full access. Download TangentCalc and solve tangent line problems the smart way. Thanks for your support, and do visit nitrio.com for more apps for your iOS devices.