ConsoleReporter

ConsoleReporter renders results to the terminal as a colour-coded table using Spectre.Console. It is part of the NBenchmark.Console package.

Setup

dotnet add package NBenchmark.Console

using NBenchmark.Console;

.WithReporter(new ConsoleReporter())

CLI usage

When the NBenchmark.Console package is referenced, ConsoleReporter self-registers via [ModuleInitializer] and becomes available through the --reporter console CLI flag:

dotnet run -- --reporter console

No explicit .WithReporter(new ConsoleReporter()) call is needed when using the CLI - the host discovers it automatically through ReporterRegistry.

Example output

Benchmark Results
Run at 2026-06-06 03:40:00 UTC - 25 warmup / 190 measured

╭──────────────────────┬─────────┬─────────┬────────┬─────────┬─────────┬─────────┬───────┬──────────╮
│ Benchmark            │ Median  │  Mean   │ Error  │ StdDev  │   P95   │   P99   │ Ratio │ Alloc/op │
├──────────────────────┼─────────┼─────────┼────────┼─────────┼─────────┼─────────┼───────┼──────────┤
│ Compute ✓            │ 300 ns  │ 275 ns  │ ±16 ns │  86 ns  │ 500 ns  │ 500 ns  │ 0.75x │    -     │
│ Baseline (baseline)  │ 400 ns  │ 376 ns  │ ±22 ns │ 114 ns  │ 500 ns  │ 900 ns  │ 1.00x │    -     │
╰──────────────────────┴─────────┴─────────┴────────┴─────────┴─────────┴─────────┴───────┴──────────╯

Ran 2 benchmark(s) in 0.0s - Significance: Mann-Whitney U (p < 0.05) - Outliers: top 5%
Error = ±95% confidence interval half-width on the mean.

When there are two or more benchmarks, a bar chart of median timings is also displayed below the table.

Columns

Column	Description
Benchmark	Name of the benchmark. Colour-coded: green (≤ 5% slower than baseline), yellow (≤ 50% slower), red (> 50% slower). Baseline is shown in bold.
Median	Median timing.
Mean	Arithmetic mean.
Error	±Margin of error on the mean at the configured confidence level.
StdDev	Sample standard deviation.
P95	95th percentile.
P99	99th percentile.
Ratio	Speed relative to the baseline. Green for faster, yellow for moderately slower, red for significantly slower.
Alloc/op	Mean heap bytes per iteration (only visible when allocation tracking is enabled).

An optional Description column appears if any benchmark has a Description set.

A ✓ next to the name indicates the difference from the baseline is statistically significant (p < 0.05). A ~ indicates it is not.

Adding progress display

ConsoleBenchmarkProgress displays warmup and measurement progress for each benchmark as it runs. It is independent of ConsoleReporter and can be used without it.

using NBenchmark.Console;

await new BenchmarkSuite("name")
    .WithIterations(200)
    .WithWarmup(25)
    .WithReporter(new ConsoleReporter())
    .WithProgress(new ConsoleBenchmarkProgress(measuredIterations: 200, warmupIterations: 25))
    .RunAsync();

Pass the same measuredIterations and warmupIterations values you gave to WithIterations and WithWarmup so the progress display shows accurate counts.

Progress output looks like:

Starting 2 benchmark(s)...
  [[Compute]] warming up (25 iterations)...
  [1/2] Compute - running (25 warmup / 200 measured)...
  [[Baseline]] warming up (25 iterations)...
  [2/2] Baseline - running (25 warmup / 200 measured)...
  Completed 2 benchmark(s).

Using with Benchmark (Quick mode)

using NBenchmark.Console;

var result = Benchmark.Run(() => MyMethod());
await result.PrintAsync();

PrintAsync runs the single result through ConsoleReporter and renders a table.

Printing markup from the summary line

The summary line at the bottom always shows the confidence level from the first successful result. If all benchmarks errored, only a list of error messages is shown.