diff --git a/lib/index.js b/lib/index.js
index 1c075a9..847334b 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -25,6 +25,10 @@ class Tag {
             '': this.defaultConfig
         }
 
+        this.translationCache = {}
+
+        this.keyCache = {}
+
         this._localizers = {
             s /*string*/: (config, v, format) => {
                 let formatted
@@ -81,6 +85,8 @@ class Tag {
     }
 
     i18nConfig({locales, translations, group, number, date, standardFormatters}) {
+        // clear translation cache
+        this.translationCache = {}
         const currentConfig = this.configs[group || ''] || this.defaultConfig
         this.configs[group || ''] = Object.assign({}, currentConfig, {
             locales: locales || currentConfig.locales,
@@ -92,24 +98,34 @@ class Tag {
     }
 
     i18n(group, config, literals, ...values) {
-        const translationKey = this._buildKey(literals)        
-        const configGroup = this.configs[config || ''] || this.defaultConfig
-        const translationString = this._getTranslation(group, configGroup, translationKey)    
+        const translationKey = this._buildKey(literals)     
+        const { configGroup, translatedKey } = this._getCachedTranslation(group, config, translationKey)   
         const typeInfoForValues = literals.slice(1).map(this._extractTypeInfo)
         const localizedValues = values.map((v, i) => this._localize(configGroup, v, typeInfoForValues[i]))
-        return this._buildMessage(translationString, ...localizedValues)
+        return this._buildMessage(translatedKey, ...localizedValues)
     }
 
     translate(group, config, key, ...values) {
-        const configGroup = this.configs[config || ''] || this.defaultConfig
-        const translationString = this._getTranslation(group, configGroup, key)  
+        const { configGroup, translatedKey } = this._getCachedTranslation(group, config, key)
         const localizedValues = values.map((v) => {
             if(v instanceof Object && v.constructor === Object) {
                 return this._localize(configGroup, v.value || '', { type: v.formatter || 's', options: v.format })
             } 
             return this._localize(configGroup, v, { type: 's', options: '' })
         })
-        return this._buildMessage(translationString, ...localizedValues)
+        return this._buildMessage(translatedKey, ...localizedValues)
+    }
+
+    _getCachedTranslation(group, config, translationKey) {
+        const cacheKey = [group || '', config || '', translationKey].join()
+        const cachedTranslation = this.translationCache[cacheKey]
+        const configGroup = this.configs[config || ''] || this.defaultConfig
+        if(cachedTranslation) {
+            return { configGroup, translatedKey: cachedTranslation }
+        }
+        const translationString = this._getTranslation(group, configGroup, translationKey)  
+        this.translationCache[cacheKey] = translationString
+        return { configGroup, translatedKey: translationString }
     }
 
     _getTranslation(group, configGroup, translationKey) {
@@ -291,11 +307,19 @@ class Tag {
 
     // e.g. this._buildKey(['', ' has ', ':c in the']) == '{0} has {1} in the bank'
     _buildKey(literals) {
+        const cacheKey = literals.join()
+        const cachedKey = this.keyCache[cacheKey]
+        if(cachedKey) {
+            return cachedKey
+        }
+
         const stripType = (s) => s.replace(typeInfoRegex, '')
         const lastPartialKey = stripType(literals[literals.length - 1])
         const prependPartialKey = (memo, curr, i) => `${stripType(curr)}\${${i}}${memo}`
 
-        return literals.slice(0, -1).reduceRight(prependPartialKey, lastPartialKey).replace(/\r\n/g, '\n')
+        const key = literals.slice(0, -1).reduceRight(prependPartialKey, lastPartialKey).replace(/\r\n/g, '\n')
+        this.keyCache[cacheKey] = key
+        return key
     }
 
     // e.g. this._formatStrings('{0} {1}!', 'hello', 'world') == 'hello world!'