diff --git a/src/ConvergenceTestWorkflow/Config.jl b/src/ConvergenceTestWorkflow/Config.jl
index f30557d7..a9cd6a4b 100644
--- a/src/ConvergenceTestWorkflow/Config.jl
+++ b/src/ConvergenceTestWorkflow/Config.jl
@@ -38,16 +38,16 @@ end
     recipe::String
     template::String
     with::Union{CutoffEnergies,MonkhorstPackGrids}
-    criteria::Quantity
+    threshold::Quantity
     io::IO = IO()
     data::Data = Data()
     cli::SoftwareConfig
-    function StaticConfig(recipe, template, with, criteria, io, data, cli)
+    function StaticConfig(recipe, template, with, threshold, io, data, cli)
         @assert recipe in ("ecut", "kmesh")
         if !isfile(template)
             @warn "I cannot find template file `$template`!"
         end
-        return new(recipe, template, with, criteria, io, data, cli)
+        return new(recipe, template, with, threshold, io, data, cli)
     end
 end
 
@@ -80,6 +80,10 @@ function _update!(conf::Conf, data::Data)
     conf.data.raw = abspath(expanduser(data.raw))
     return conf
 end
+function _update!(conf::Conf, threshold::Quantity)
+    conf.threshold = threshold
+    return conf
+end
 
 function expand(config::StaticConfig, calculation::Calculation)
     conf = Conf()
@@ -89,6 +93,7 @@ function expand(config::StaticConfig, calculation::Calculation)
     _update!(conf, config.with)
     _update!(conf, config.io, config.with)
     _update!(conf, config.data)
+    _update!(conf, config.threshold)
     return conf
 end
 
diff --git a/src/ConvergenceTestWorkflow/actions.jl b/src/ConvergenceTestWorkflow/actions.jl
index b9dd83ff..203f4c64 100644
--- a/src/ConvergenceTestWorkflow/actions.jl
+++ b/src/ConvergenceTestWorkflow/actions.jl
@@ -28,10 +28,11 @@ end
 struct TestConvergence{T} <: Action{T}
     calculation::T
 end
-(::TestConvergence)(data) = isconvergent(data)
+(::TestConvergence)(threshold) = Base.Fix2(isconvergent, threshold)
 
-function isconvergent(a)
-    terms = abs.(diff(collect(a)))
-    x, y, z = last(terms, 3)
-    return all(0 <= r < 1 for r in (y / x, z / y))
+function isconvergent(iter, threshold)
+    last3 = last(sort(iter; by=first), 3)  # Sort a `Set` of `Pair`s by the keys, i.e., increasing cutoff energies
+    min, max = extrema(last.(last3))  # Get the minimum and maximum energies from the last 3 pairs
+    range = abs(max - min)
+    return zero(range) <= range <= threshold
 end
diff --git a/src/ConvergenceTestWorkflow/think.jl b/src/ConvergenceTestWorkflow/think.jl
index 0fb88d46..e449afe0 100644
--- a/src/ConvergenceTestWorkflow/think.jl
+++ b/src/ConvergenceTestWorkflow/think.jl
@@ -10,7 +10,7 @@ think(action::CreateInput, conf::Conf) =
 think(action::ExtractData, conf::Conf) =
     collect(Thunk(action, file) for file in last.(conf.io))
 think(action::SaveData, conf::Conf) = Thunk(action(conf.data.raw))
-think(action::TestConvergence, ::Conf) = Thunk(action)
+think(action::TestConvergence, conf::Conf) = Thunk(action, conf.threshold)
 function think(action::Action{T}, config::StaticConfig) where {T}
     config = expand(config, T())
     return think(action, config::Conf)