Grade Calculator
Enter Level 1, Level 2, and Length to calculate grade.
| # | Level 1 (m) | Level 2 (m) | Length (m) | Grade (%) | Slope (1 in ?) |
|---|
Note: +grade is up, −grade is down
Grade Difference Calculator
Grade inputs
Grade 1
Grade 2
Results
Grade 1
—
percent
Grade 2
—
percent
Difference
—
percent
Angle
—
degrees
Quick reference
| Grade difference (%) | Angle (degrees) |
|---|
Pipe Grade Converter
Single conversion
Fall ratio (1 in X)
Grade (%)
Grade
—
percent
Fall ratio
—
1 in X
Fall per metre
—
mm/m
Fall per metre
—
m/m
Batch conversion 1 in X → %
Enter one ratio per line (just the X value, e.g. 40)
Results
Common grades reference
| Fall ratio | Grade (%) | mm/m |
|---|
Level Calculator
Enter Level 1, Grade (1 in ?), and Length to calculate Level 2.
| # | Level 1 (m) | Grade (1 in ?) | Length (m) | Level 2 (m) | Change in Level (m) |
|---|
Note: +grade is up, −grade is down. Enter Grade as positive (uphill) or negative (downhill).
Grade Converter
Grade (%)
Grade (1 in ?)
Level Interpolation Calculator
Enter both end levels, the total length, and the distance from Level 1 to find the level at any intermediate point.
| # | Level 1 (m) | Level 2 (m) | Total Length (m) | Dist. from L1 (m) | Level at Point (m) |
|---|
Formula: Level at Point = L1 + (L2 − L1) × (Distance from L1 ÷ Total Length)
How it works
The calculator linearly interpolates between Level 1 and Level 2. The point level rises or falls in proportion to how far along the run the selected distance falls.
LS Level Calculator
Drawing Settings
Scale (from table)
Datum (m)
These values apply to all rows. Change them if reading from a different drawing or datum.
Enter the length measured from the datum on the drawing for each point.
| # | Length from Datum (mm) | Existing Level (m) optional | Level (m) | Depth (m) |
|---|
Formula: Level = Datum + (Length ÷ Scale) · Depth = Existing Level − Level
LS Vertical Scale Reference
| LS Vertical Scale | Value for 'Scale' Input |
|---|---|
| 1:20 | 50 |
| 1:25 | 40 |
| 1:50 | 20 |
| 1:100 | 10 |
Formula: Scale value = 1000 ÷ vertical scale denominator
LS Distance Calculator
Drawing Settings
Scale (from table)
Datum (m)
These values apply to all rows. Change them if drawing to a different scale or datum.
Enter a level for each point to get the distance to draw above the datum line.
| # | Level (m) | Distance from Datum (mm) |
|---|
Formula: Distance = (Level − Datum) × Scale · Red values fall below the datum line.
LS Vertical Scale Reference
| LS Vertical Scale | Value for 'Scale' Input |
|---|---|
| 1:20 | 50 |
| 1:25 | 40 |
| 1:50 | 20 |
| 1:100 | 10 |
Formula: Scale value = 1000 ÷ vertical scale denominator
Length Calculator
Enter Level 1, Level 2, and Grade (1 in ?) to calculate Length.
| # | Level 1 (m) | Level 2 (m) | Grade (1 in ?) | Length (m) |
|---|
Note: Length = (Level 2 − Level 1) × Grade (1 in ?). Negative grade inputs indicate a downhill run.
Grade Converter
Grade (%)
Grade (1 in ?)
Invert Level Chain
Chain Settings
Starting invert level (m)
Default drop at structures
Grade entered as
Starting invert is the upstream invert of pipe 1. The default drop applies at every structure after pipe 1 unless a row has its own drop entered.
Enter each pipe in order, from upstream to downstream.
| # | US Structure | Length (m) | Grade (%) | Drop at US (mm) | US IL (m) | DS IL (m) | Fall (m) |
|---|
Formula: DS IL = US IL − Fall · next US IL = previous DS IL − Drop. Enter positive grades for pipes falling downstream; red values are adverse (rising) grades. The chain stops at the first incomplete row.
Summary
Total length
—
m
Total fall (incl. drops)
—
m
Final DS invert
—
m
Pipe Cover Calculator
Check Settings
Minimum cover
Default pipe OD
Default wall thickness
Minimum cover depends on the authority, pipe type and location (e.g. trafficked vs non-trafficked). Enter the value that applies to your job. Row OD and wall values override the defaults.
Enter the surface level and invert level at each check point.
| # | Location | Surface Level (m) |
Invert Level (m) |
OD (mm) |
Wall (mm) |
Top of Pipe (m) |
Cover (m) |
Depth to IL (m) |
|---|
Formula: Top of Pipe = IL − Wall + OD · Cover = SL − Top of Pipe · Depth to IL = SL − IL
How it's measured
Cover is measured from the surface to the outside top of the pipe barrel. The invert is the inside bottom of the pipe, so the top of pipe sits one outside diameter above the invert, less one wall thickness.