AtlasCalcsUtility Calculation Suite
2026-07-30 8 min

Total Runout Calculator

Calculate total runout from axial and radial readings along a surface. Evaluate composite surface variation per ASME Y14.5.

Calculator

Unit System
Axial Readings (mm)
Radial Readings (mm)
Number of Axial Positions
Tolerance Value (mm)
Datum Axis

Results

Optimal

Total Runout

0.0300mm

Maximum surface variation - controls entire surface simultaneously

Max Radial Runout

0.0300mm

Maximum radial TIR across all axial positions

Axial Runout (TIR)

0.0150mm

Total axial variation from axial readings

Deviation Ratio

0.6000

Total runout divided by tolerance value

Visualizations

Results Overview

0mmTotal Runout
0mmMax Radial Runout
0mmAxial Runout
0.6mmDeviation Ratio

Formula

Total runout controls the entire surface simultaneously, combining both axial and radial variations. It is the most comprehensive runout control in GD&T.

Total_Runout = max(Axial_TIR, max_over_positions(Radial_TIR_each))

Alternative Form

Deviation_Ratio = Total_Runout / Tolerance_Value

Variables

SymbolNameUnitDescription
Axial_TIRAxial Total Indicator ReadingmmDifference between max and min axial readings
Radial_TIR_iRadial TIR at Axial Position immFull indicator movement at each axial position
TRTotal RunoutmmMaximum of all TIR values (axial and radial)

Explanation

Total runout is a composite GD&T control that limits the total variation of an entire surface when the part is rotated 360° about a datum axis. Unlike circular runout which only checks individual cross-sections, total runout requires the indicator to traverse along the surface while the part rotates, capturing the worst-case variation across the entire feature.

Derivation

The total runout calculation evaluates two components: (1) Axial TIR - the variation of axial readings along the surface axis, and (2) Radial TIR at each axial position - the radial variation at each cross-section. The total runout is the maximum of all these values, representing the worst-case surface deviation from the true datum axis.

Step-by-Step Calculation

Follow each step to understand how the result is calculated from your inputs.

Step 1

Mount the part on a precision rotating fixture aligned to the specified datum axis.

Datum Axis:A-B (combined datum)
Fixture:Precision rotary table or between centers
Result: Part secured and aligned
Step 2

Take axial readings along the surface to evaluate axial variation.

Readings:0.01, 0.02, 0.015, 0.025, 0.02
Intermediate: Axial TIR = 0.0150 mm
Result: Axial runout component: 0.0150 mm
Step 3

Take radial readings at 3 axial positions (100.0000% of total).

Radial TIR per position = max(pos_readings) - min(pos_readings)
Result: Max radial runout component: 0.0300 mm
Step 4

Compute total runout and compare to tolerance.

Total Runout = max(Axial TIR, Max Radial TIR)
Axial Component:0.0150 mm
Radial Component:0.0300 mm
Intermediate: Total = max(0.0150, 0.0300)
Result: PASS - Total Runout 0.0300 mm within 0.05 mm
Final Answer
0.0300

Worked Examples

See how the calculator works with different scenarios.

Scenario

A precision ground cylinder with total runout tolerance of 0.05 mm to datum A-B. Axial readings: 0.01, 0.02, 0.015, 0.025, 0.02 mm. Radial readings at 3 positions: P1: 0.02, 0.03, 0.01; P2: 0.025, 0.035, 0.015; P3: 0.02, 0.03, 0.01 mm.

Inputs

Axial Readings:0.01, 0.02, 0.015, 0.025, 0.02 mm
Radial (3 positions):P1: 0.03-0.01=0.02, P2: 0.035-0.015=0.02, P3: 0.03-0.01=0.02
Tolerance:0.05 mm

Calculation

Axial TIR = 0.025 - 0.01 = 0.015 mm Max Radial TIR = max(0.02, 0.02, 0.02) = 0.02 mm Total Runout = max(0.015, 0.02) = 0.02 mm

Result

Total Runout: 0.0200 mm — PASS

Interpretation

The cylinder meets the total runout specification with a deviation ratio of 0.4. The surface quality is consistent along the entire length.

Understanding Your Result

Your Result: Total Runout: 0.0300 mm

Typical range: Precision spindles: 0.003-0.015 mm. Hydraulic cylinders: 0.02-0.05 mm. General machined shafts: 0.05-0.15 mm. Heavy equipment: 0.10-0.30 mm.

What This Means

Total runout is the most comprehensive runout control in GD&T. It limits the total variation of an entire surface referenced to a datum axis, simultaneously controlling roundness, straightness, coaxiality, taper, and surface profile along the entire length.

Why It Matters

Total runout ensures that rotating surfaces maintain consistent dimensional accuracy along their entire length. This is critical for bearings, seals, pistons, and other components where the full surface contacts another part during rotation.

Professional Interpretation

Total runout is more restrictive than circular runout because it evaluates the entire surface simultaneously. A part may pass circular runout at every cross-section but fail total runout if the surface has taper or curvature. Total runout is specified when the functional surface must maintain consistent geometry along its entire length during rotation.

Recommendations

  • •Use total runout when the full surface engages with a mating part during rotation
  • •Specify total runout for seal surfaces, bearing journals, and piston surfaces
  • •Consider circular runout instead if only individual cross-sections are critical
  • •Ensure the indicator traverses smoothly along the entire surface
  • •Use multiple axial positions to capture surface variation patterns
  • •Document the measurement path and number of axial positions
  • •Verify datum axis alignment before starting measurements

Educational Content

Introduction

Total runout is a geometric dimensioning and tolerancing (GD&T) control defined by ASME Y14.5 that limits the total surface variation of a feature when rotated 360° about a datum axis. Unlike circular runout, total runout applies simultaneously to all circular elements of the surface.

Concept Explanation

Total runout is evaluated by rotating the part 360° about the datum axis while a dial indicator traverses the entire surface along the axis. The indicator records the combined effect of all surface irregularities - roundness errors, taper, curvature, and surface finish variations - across the full surface. Total runout equals the maximum indicator reading minus the minimum reading over the entire measurement.

Applications

▸Hydraulic and pneumatic cylinder bores and piston rods
▸Long shafts with multiple bearing journals
▸Seal mating surfaces for rotating equipment
▸Printing and converting roller surfaces
▸Extruder screw and barrel surfaces
▸Turbine shaft surfaces
▸Automotive transmission shafts

Benefits

  • •Comprehensive surface quality assessment
  • •Detects axial variations (taper, curvature, straightness) missed by circular runout
  • •Single setup measurement for complete surface evaluation
  • •Internationally accepted per ASME and ISO standards
  • •Directly correlates to functional performance in many applications
  • •Provides clear pass/fail criteria for production inspection

Limitations

  • •More time-consuming than circular runout due to surface traversal
  • •Requires specialized fixtures for consistent traversal
  • •May be overly restrictive if only individual cross-sections are functional
  • •Sensitive to surface finish variations that may not affect function
  • •Cannot isolate specific error sources

Best Practices

  • •Use motorized rotary tables with controlled rotation speed
  • •Traverse the indicator at a constant speed along the surface
  • •Use data acquisition systems for automated data collection
  • •Apply light, consistent contact pressure throughout traversal
  • •Perform multiple traverses and average the results
  • •Calibrate the indicator before and after measurement
  • •Document the entire measurement path and data points

Common Misconceptions

Myth: Total runout is the same as circular runout averaged over the surface.
Truth: Total runout is NOT an average. It captures the worst-case deviation anywhere on the entire surface.
Myth: Total runout is only for cylindrical surfaces.
Truth: Total runout can also be applied to conical surfaces and other surfaces of revolution.
Myth: Good circular runout guarantees good total runout.
Truth: A part can have perfect circular runout at every cross-section but have a tapered surface that fails total runout.

Practical Tips

  • •Total runout is more restrictive than circular runout - account for this in design tolerancing
  • •Use at least 5 axial positions for long surfaces to capture taper and curvature
  • •The axial traverse rate should not exceed the indicator response time
  • •Zero the indicator at the lowest point of the entire surface, not at a single cross-section
  • •For very long surfaces, consider using multiple indicator positions instead of traversing
  • •Record the location of maximum deviation to guide corrective actions
  • •Combine total runout with surface finish specifications for complete surface control

Common Mistakes

Confusing total runout with circular runout
Circular runout applies at individual cross-sections; total runout applies to the entire surface simultaneously.
Taking radial readings at too few axial positions
Use at least 3 axial positions minimum. More positions provide better surface characterization.
Using incorrect datum reference
Clearly define the datum axis on the drawing and establish it correctly during measurement.
Not allowing indicator to traverse the full surface
Traverse from one end of the tolerance zone to the other to capture the full surface variation.
Misinterpreting deviation ratio
A ratio ≤ 1.0 means conformance. Document the ratio for statistical process monitoring.

Assumptions

This calculator makes the following assumptions to provide estimates:

Full Surface Traversal: The indicator traverses the entire surface from one end to the other during rotation.
Rigid Part: The part does not deflect under indicator contact force or clamping.
Ideal Rotation: Rotation is about the true datum axis with minimal spindle error.
Uniform Traverse Speed: The indicator traverses at a speed that allows accurate reading capture.

Limitations

Be aware of these limitations when using this calculator:

Traverse Mechanism Quality: Results depend on the accuracy and repeatability of the indicator traverse mechanism.
Surface Finish Sensitivity: Very rough surfaces may produce erratic readings that mask true geometric errors.
Single Setup Constraint: All measurements must be taken in a single setup to maintain datum reference consistency.
Part Length Limitations: Very long parts may exceed the capacity of standard runout measurement fixtures.

Frequently Asked Questions

Answers to common questions about this calculator.

What is total runout?
Total runout is a GD&T control that limits the total surface variation of an entire feature when rotated 360° about a datum axis. It controls the complete surface simultaneously.
How is total runout different from circular runout?
Circular runout checks individual cross-sections one at a time. Total runout evaluates the entire surface simultaneously as the indicator traverses along the axis.
How is total runout measured?
The part rotates 360° about the datum axis while a dial indicator traverses the entire surface. The total runout is the difference between the highest and lowest readings across the full surface.
When should I use total runout?
Use total runout when the entire surface engages with a mating part during rotation, such as seal surfaces, bearing journals, and piston rods.
What standards govern total runout?
ASME Y14.5 (US) and ISO 1101 (International) define total runout tolerancing rules, symbols, and measurement methods.
What causes failure in total runout?
Common causes: bent shafts, taper from machining, curvature, misalignment between centers, uneven material removal, and thermal distortion.
How many axial positions are needed?
At least 3 axial positions for short surfaces, 5+ for longer surfaces. More positions provide better surface characterization.
What is the relationship between circular and total runout?
Total runout is always ≥ circular runout at any cross-section. A part passing total runout automatically passes circular runout.
Can total runout be applied to conical surfaces?
Yes, total runout can be applied to any surface of revolution including cones, contoured surfaces, and tapered cylinders.
What is a typical total runout tolerance?
Precision: 0.003-0.015 mm. General machining: 0.05-0.15 mm. Heavy equipment: 0.10-0.30 mm.
How does total runout affect manufacturing cost?
Total runout tolerances are typically 2-3x more expensive to achieve than equivalent circular runout due to the more stringent surface requirements.
What is the difference between axial and radial runout?
Axial runout measures variation along the axis (face wobble). Radial runout measures variation perpendicular to the axis (diameter variation).
Can total runout be checked manually?
Yes, but manual traversal is operator-dependent. Automated measurement provides more repeatable results.
How does part geometry affect total runout?
Length-to-diameter ratio, surface hardness, and part rigidity all influence total runout measurement results.
What is the tolerance zone for total runout?
The tolerance zone is a cylindrical volume. The entire surface must lie within this zone as the part rotates 360°.
How do I convert circular runout to total runout?
There is no direct conversion. Total runout is typically 1.5-3x larger than circular runout for the same part, depending on surface geometry.
What equipment is needed for total runout measurement?
Rotary table or between-centers fixture, dial indicator with resolution 10x the tolerance, and a traversing mechanism or carriage.
How does temperature affect total runout?
Temperature gradients along the surface can cause apparent runout due to differential thermal expansion. Measure at thermal equilibrium.
What is total indicator reading (TIR)?
TIR is another term for Full Indicator Movement - the total range of indicator readings. In total runout, TIR is measured over the entire surface.
Can total runout be applied to threaded surfaces?
Total runout is generally not applied to threads. Thread-specific controls like pitch diameter runout are used instead.
How do I interpret total runout on a drawing?
The feature control frame shows the total runout symbol, tolerance value, and datum references (e.g., ⟂ | 0.05 | A-B).
What is the difference between runout and profile?
Runout controls surface variation during rotation about a datum axis. Profile controls surface form independent of rotation.
How does surface finish affect total runout?
Rough surfaces can significantly increase total runout values. A 0.001 mm surface finish can contribute 0.003-0.005 mm to total runout.
What is the cost of total runout measurement?
Total runout measurement typically costs 2-3x more than circular runout due to longer inspection time and specialized fixtures.
Can total runout be applied to assemblies?
Yes, total runout can be specified on assembled components to ensure functional performance of the complete assembly.
How do I choose between total and circular runout?
Choose total runout when the entire surface must be controlled. Choose circular runout when only individual cross-sections are functionally critical.
What is the effect of datum selection on total runout?
Different datum selections produce different measurement results. Always measure per the drawing datum specification.
How do I document total runout results?
Record datum references, tolerance, number of axial positions, TIR at each position, total runout, deviation ratio, and pass/fail status.
What is the repeatability of total runout measurement?
Repeatability depends on fixturing, indicator quality, and operator technique. Expect ±10% of measured value for manual measurements.
Can software calculate total runout?
CMM software and dedicated runout measurement systems can automatically calculate total runout from point cloud data.
What is the future of total runout measurement?
Laser scanning and non-contact sensors are replacing dial indicators for automated, high-speed total runout measurement.

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Glossary

Technical terms used in mortgage calculations explained in plain language.

Axial Runout
Surface variation measured parallel to the datum axis (face wobble), typically on surfaces perpendicular to the axis.
Circular Runout
GD&T control limiting radial variation at individual cross-sections, less comprehensive than total runout.
Datum Axis
The theoretically exact axis about which the surface rotates, established by datum features or precision fixturing.
Deviation Ratio
Ratio of measured total runout to specified tolerance, used as a process capability indicator.
Full Indicator Movement (FIM)
The algebraic difference between maximum and minimum indicator readings, also called TIR.
Radial Runout
Surface variation measured perpendicular to the datum axis, captures out-of-round and eccentricity.
Surface of Revolution
A surface generated by rotating a line or curve about an axis, such as cylinders, cones, and contoured surfaces.
Taper
A progressive change in diameter along the axis of a cylindrical feature, detected by total runout measurement.
TIR
Total Indicator Reading - synonym for FIM, the full range of indicator movement.
Total Runout
GD&T control applying runout simultaneously to the entire surface, combining axial and radial variations.
Traverse
The movement of an indicator along the surface axis during total runout measurement.
Tolerance Zone
The specified volume within which the entire surface must lie, defined by the total runout tolerance value.

Authoritative References

Trusted sources and standards referenced by this calculator.

Applicable Standards

ASME Y14.5ISO 1101ISO 2768ISO 1938ASME B89.1.12ISO/TS 15530VDA 5

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Page Information

Last Updated:

2026-07-30

Version:

2.0.0

License:

Free to use for educational and professional purposes.