diff --git a/src/ja/readmangaat/build.gradle b/src/ja/readmangaat/build.gradle
new file mode 100644
index 000000000..371c98889
--- /dev/null
+++ b/src/ja/readmangaat/build.gradle
@@ -0,0 +1,8 @@
+ext {
+    extName = 'ReadManga.at'
+    extClass = '.ReadMangaAt'
+    extVersionCode = 1
+    isNsfw = true
+}
+
+apply from: "$rootDir/common.gradle"
diff --git a/src/ja/readmangaat/res/mipmap-hdpi/ic_launcher.png b/src/ja/readmangaat/res/mipmap-hdpi/ic_launcher.png
new file mode 100644
index 000000000..ac31cb683
Binary files /dev/null and b/src/ja/readmangaat/res/mipmap-hdpi/ic_launcher.png differ
diff --git a/src/ja/readmangaat/res/mipmap-mdpi/ic_launcher.png b/src/ja/readmangaat/res/mipmap-mdpi/ic_launcher.png
new file mode 100644
index 000000000..2ed1177d1
Binary files /dev/null and b/src/ja/readmangaat/res/mipmap-mdpi/ic_launcher.png differ
diff --git a/src/ja/readmangaat/res/mipmap-xhdpi/ic_launcher.png b/src/ja/readmangaat/res/mipmap-xhdpi/ic_launcher.png
new file mode 100644
index 000000000..48857e0b1
Binary files /dev/null and b/src/ja/readmangaat/res/mipmap-xhdpi/ic_launcher.png differ
diff --git a/src/ja/readmangaat/res/mipmap-xxhdpi/ic_launcher.png b/src/ja/readmangaat/res/mipmap-xxhdpi/ic_launcher.png
new file mode 100644
index 000000000..4e3498edc
Binary files /dev/null and b/src/ja/readmangaat/res/mipmap-xxhdpi/ic_launcher.png differ
diff --git a/src/ja/readmangaat/res/mipmap-xxxhdpi/ic_launcher.png b/src/ja/readmangaat/res/mipmap-xxxhdpi/ic_launcher.png
new file mode 100644
index 000000000..44e2174d4
Binary files /dev/null and b/src/ja/readmangaat/res/mipmap-xxxhdpi/ic_launcher.png differ
diff --git a/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/Dto.kt b/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/Dto.kt
new file mode 100644
index 000000000..01adde907
--- /dev/null
+++ b/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/Dto.kt
@@ -0,0 +1,22 @@
+package eu.kanade.tachiyomi.extension.ja.readmangaat
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+class LatestDto(
+    val mes: String,
+    val going: String,
+)
+
+@Serializable
+class InfoDto(
+    val mes: String,
+)
+
+@Serializable
+class ImageResponseDto(
+    val mes: String,
+    val going: Int,
+    @SerialName("img_index") val imgIndex: Int,
+)
diff --git a/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/ReadMangaAt.kt b/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/ReadMangaAt.kt
new file mode 100644
index 000000000..450c98c74
--- /dev/null
+++ b/src/ja/readmangaat/src/eu/kanade/tachiyomi/extension/ja/readmangaat/ReadMangaAt.kt
@@ -0,0 +1,323 @@
+package eu.kanade.tachiyomi.extension.ja.readmangaat
+
+import eu.kanade.tachiyomi.network.GET
+import eu.kanade.tachiyomi.network.POST
+import eu.kanade.tachiyomi.network.interceptor.rateLimit
+import eu.kanade.tachiyomi.source.model.Filter
+import eu.kanade.tachiyomi.source.model.FilterList
+import eu.kanade.tachiyomi.source.model.MangasPage
+import eu.kanade.tachiyomi.source.model.Page
+import eu.kanade.tachiyomi.source.model.SChapter
+import eu.kanade.tachiyomi.source.model.SManga
+import eu.kanade.tachiyomi.source.online.ParsedHttpSource
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.decodeFromStream
+import okhttp3.FormBody
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import okhttp3.Request
+import okhttp3.Response
+import org.jsoup.Jsoup
+import org.jsoup.nodes.Document
+import org.jsoup.nodes.Element
+import uy.kohesive.injekt.injectLazy
+import java.text.ParseException
+import java.text.SimpleDateFormat
+import java.util.Locale
+
+class ReadMangaAt : ParsedHttpSource() {
+
+    override val name = "ReadManga.at"
+
+    override val baseUrl = "https://readmanga.at"
+
+    override val lang = "ja"
+
+    override val supportsLatest = true
+
+    override val client = network.cloudflareClient.newBuilder()
+        .rateLimit(2)
+        .build()
+
+    override fun headersBuilder() = super.headersBuilder()
+        .add("Referer", "$baseUrl/")
+
+    private val ajaxUrl = "$baseUrl/wp-admin/admin-ajax.php"
+
+    private val apiHeaders by lazy { apiHeadersBuilder().build() }
+
+    private fun apiHeadersBuilder() = headersBuilder().apply {
+        add("Accept", "application/json, text/javascript, */*; q=0.01")
+        add("Host", baseUrl.toHttpUrl().host)
+        add("Origin", baseUrl)
+        add("X-Requested-With", "XMLHttpRequest")
+    }
+
+    private val json: Json by injectLazy()
+
+    private val dateFormat = SimpleDateFormat("M月 d, yyyy", Locale.JAPANESE)
+
+    private val chapterRegex = Regex("""\bp:\s*(\d+)""")
+
+    // ============================== Popular ===============================
+
+    override fun popularMangaRequest(page: Int): Request = GET(baseUrl, headers)
+
+    override fun popularMangaSelector(): String = "div:has(>div:contains(Popular)) > div > div[class~=entry]"
+
+    override fun popularMangaFromElement(element: Element): SManga = SManga.create().apply {
+        with(element.selectFirst("h4 > a")!!) {
+            setUrlWithoutDomain(attr("abs:href"))
+            title = text()
+        }
+    }
+
+    override fun popularMangaNextPageSelector(): String? = null
+
+    // =============================== Latest ===============================
+
+    override fun latestUpdatesRequest(page: Int): Request {
+        return if (page > 1) {
+            val apiBody = FormBody.Builder().apply {
+                add("action", "z_do_ajax")
+                add("_action", "loadmore")
+                add("p", page.toString())
+            }.build()
+
+            POST(ajaxUrl, apiHeaders, apiBody)
+        } else {
+            GET(baseUrl, headers)
+        }
+    }
+
+    override fun latestUpdatesSelector(): String = "div.row > div.col-sm-6"
+
+    override fun latestUpdatesFromElement(element: Element): SManga = SManga.create().apply {
+        with(element.selectFirst("a:has(img)")!!) {
+            thumbnail_url = selectFirst("img")!!.attr("abs:src")
+            setUrlWithoutDomain(attr("abs:href"))
+            title = attr("title")
+        }
+    }
+
+    override fun latestUpdatesNextPageSelector(): String = ".text-center > a:contains(Load More)"
+
+    override fun latestUpdatesParse(response: Response): MangasPage {
+        if (response.request.method == "GET") {
+            return super.latestUpdatesParse(response)
+        }
+
+        val data = response.parseAs<LatestDto>()
+        val mangaList = Jsoup.parseBodyFragment(data.mes)
+            .select("div.col-sm-6")
+            .map(::latestUpdatesFromElement)
+        val hasNextPage = data.going == "yes"
+
+        return MangasPage(mangaList, hasNextPage)
+    }
+
+    // =============================== Search ===============================
+
+    override fun searchMangaRequest(page: Int, query: String, filters: FilterList): Request {
+        val url = baseUrl.toHttpUrl().newBuilder().apply {
+            val genreFilter = filters.filterIsInstance<GenreFilter>().first()
+
+            if (query.isNotBlank()) {
+                addQueryParameter("s", query)
+            } else {
+                addPathSegment("genres")
+                addEncodedPathSegment(genreFilter.toUriPart())
+            }
+
+            addPathSegment("")
+            if (page > 1) {
+                addPathSegment("page")
+                addPathSegment(page.toString())
+                addPathSegment("")
+            }
+        }.build()
+
+        return GET(url, headers)
+    }
+
+    override fun searchMangaSelector(): String = ".row > .col-6 > .entry-ma"
+
+    override fun searchMangaFromElement(element: Element): SManga =
+        latestUpdatesFromElement(element)
+
+    override fun searchMangaNextPageSelector(): String = ".pagination > span.current + a"
+
+    // =============================== Filters ==============================
+
+    override fun getFilterList(): FilterList = FilterList(
+        Filter.Header("Note: ignored when using text search"),
+        Filter.Separator(),
+        GenreFilter(),
+    )
+
+    open class UriPartFilter(displayName: String, val vals: Array<Pair<String, String>>) :
+        Filter.Select<String>(displayName, vals.map { it.first }.toTypedArray()) {
+        fun toUriPart() = vals[state].second
+    }
+
+    class GenreFilter : UriPartFilter(
+        "Genre",
+        arrayOf(
+            Pair("Ecchi", "ecchi"),
+            Pair("SF.ファンタジー", "sf-%e3%83%95%e3%82%a1%e3%83%b3%e3%82%bf%e3%82%b8%e3%83%bc"),
+            Pair("お嬢様・令嬢", "%e3%81%8a%e5%ac%a2%e6%a7%98%e3%83%bb%e4%bb%a4%e5%ac%a2"),
+            Pair("アドベンチャ", "%e3%82%a2%e3%83%89%e3%83%99%e3%83%b3%e3%83%81%e3%83%a3"),
+            Pair("ゲーム", "%e3%82%b2%e3%83%bc%e3%83%a0"),
+            Pair("サブカル・個性派", "%e3%82%b5%e3%83%96%e3%82%ab%e3%83%ab%e3%83%bb%e5%80%8b%e6%80%a7%e6%b4%be"),
+            Pair("ショタコン", "%e3%82%b7%e3%83%a7%e3%82%bf%e3%82%b3%e3%83%b3"),
+            Pair("バスケットボール", "%e3%83%90%e3%82%b9%e3%82%b1%e3%83%83%e3%83%88%e3%83%9c%e3%83%bc%e3%83%ab"),
+            Pair("バトル", "%e3%83%90%e3%83%88%e3%83%ab"),
+            Pair("バレーボール", "%e3%83%90%e3%83%ac%e3%83%bc%e3%83%9c%e3%83%bc%e3%83%ab"),
+            Pair("ピューター", "%e3%83%94%e3%83%a5%e3%83%bc%e3%82%bf%e3%83%bc"),
+            Pair("ミステリー・サスペンス", "%e3%83%9f%e3%82%b9%e3%83%86%e3%83%aa%e3%83%bc%e3%83%bb%e3%82%b5%e3%82%b9%e3%83%9a%e3%83%b3%e3%82%b9"),
+            Pair("ラブラブ・あまあま", "%e3%83%a9%e3%83%96%e3%83%a9%e3%83%96%e3%83%bb%e3%81%82%e3%81%be%e3%81%82%e3%81%be"),
+            Pair("三角関係", "%e4%b8%89%e8%a7%92%e9%96%a2%e4%bf%82"),
+            Pair("会社", "%e4%bc%9a%e7%a4%be"),
+            Pair("俺様・S彼", "%e4%bf%ba%e6%a7%98%e3%83%bbs%e5%bd%bc"),
+            Pair("兄弟", "%e5%85%84%e5%bc%9f"),
+            Pair("制服", "%e5%88%b6%e6%9c%8d"),
+            Pair("前世", "%e5%89%8d%e4%b8%96"),
+            Pair("天使・悪魔", "%e5%a4%a9%e4%bd%bf%e3%83%bb%e6%82%aa%e9%ad%94"),
+            Pair("妊婦", "%e5%a6%8a%e5%a9%a6"),
+            Pair("宗教", "%e5%ae%97%e6%95%99"),
+            Pair("悪役令嬢", "%e6%82%aa%e5%bd%b9%e4%bb%a4%e5%ac%a2"),
+            Pair("擬人化", "%e6%93%ac%e4%ba%ba%e5%8c%96"),
+            Pair("短編", "%e7%9f%ad%e7%b7%a8"),
+            Pair("職業・ビジネス", "%e8%81%b7%e6%a5%ad%e3%83%bb%e3%83%93%e3%82%b8%e3%83%8d%e3%82%b9"),
+            Pair("致命的な", "%e8%87%b4%e5%91%bd%e7%9a%84%e3%81%aa"),
+            Pair("萌え", "%e8%90%8c%e3%81%88"),
+            Pair("超能力日常", "%e8%b6%85%e8%83%bd%e5%8a%9b%e6%97%a5%e5%b8%b8"),
+            Pair("電子特典付き", "%e9%9b%bb%e5%ad%90%e7%89%b9%e5%85%b8%e4%bb%98%e3%81%8d"),
+        ),
+    )
+
+    // =========================== Manga Details ============================
+
+    override fun mangaDetailsParse(document: Document): SManga = SManga.create().apply {
+        thumbnail_url = document.selectFirst(".main-thumb > img[src]")!!.attr("abs:src")
+
+        with(document.selectFirst("div.row[class~=mb] > .col")!!) {
+            title = selectFirst(".name")!!.text()
+            status = selectFirst("span").parseStatus()
+        }
+
+        val id = document.selectFirst("a[data-t]")!!.attr("data-t")
+        val apiHeaders = apiHeadersBuilder().apply {
+            set("Referer", document.location())
+        }.build()
+
+        // Genres
+        val genresBody = FormBody.Builder().apply {
+            add("action", "z_do_ajax")
+            add("_action", "load_all_genres")
+            add("t", id)
+        }.build()
+
+        val genreDto = client.newCall(
+            POST(ajaxUrl, apiHeaders, genresBody),
+        ).execute().parseAs<InfoDto>()
+        genre = Jsoup.parseBodyFragment(genreDto.mes)
+            .select("a")
+            .joinToString { it.text() }
+
+        // Desc
+        val descBody = FormBody.Builder().apply {
+            add("action", "z_do_ajax")
+            add("_action", "load_tag_desc")
+            add("t", id)
+        }.build()
+        description = client.newCall(
+            POST(ajaxUrl, apiHeaders, descBody),
+        ).execute().parseAs<InfoDto>().mes
+    }
+
+    private fun Element?.parseStatus(): Int = when (this?.text()?.lowercase()) {
+        "ongoing" -> SManga.ONGOING
+        "dropped" -> SManga.CANCELLED
+        "paused" -> SManga.ON_HIATUS
+        "completed" -> SManga.COMPLETED
+        else -> SManga.UNKNOWN
+    }
+
+    // ============================== Chapters ==============================
+
+    override fun chapterListSelector(): String = ".row > .col-sm-6 > .entry-chapter"
+
+    override fun chapterFromElement(element: Element): SChapter = SChapter.create().apply {
+        date_upload = try {
+            element.selectFirst(".date")?.text()?.let {
+                dateFormat.parse(it)!!.time
+            } ?: 0L
+        } catch (_: ParseException) {
+            0L
+        }
+        with(element.selectFirst("a")!!) {
+            name = text()
+            setUrlWithoutDomain(attr("abs:href"))
+        }
+    }
+
+    // =============================== Pages ================================
+
+    override fun pageListParse(document: Document): List<Page> {
+        val script = document.selectFirst("script:containsData(decode_images)")?.data()
+            ?: throw Exception("Unable to find script")
+        val id = chapterRegex.find(script)?.groupValues?.get(1)
+            ?: throw Exception("Unable to get chapter id")
+
+        var going = 1
+        var imgIndex = 0
+        val pageList = mutableListOf<Page>()
+        val apiHeaders = apiHeadersBuilder().apply {
+            set("Referer", document.location())
+        }.build()
+
+        while (going == 1) {
+            val pagesBody = FormBody.Builder().apply {
+                add("action", "z_do_ajax")
+                add("_action", "decode_images")
+                add("p", id)
+                add("img_index", imgIndex.toString())
+            }.build()
+
+            val data = client.newCall(
+                POST(ajaxUrl, apiHeaders, pagesBody),
+            ).execute().parseAs<ImageResponseDto>()
+
+            imgIndex = data.imgIndex
+            going = if (data.mes.isNotBlank()) data.going else 0
+
+            Jsoup.parseBodyFragment(data.mes).select("img[src]").forEachIndexed { index, element ->
+                pageList.add(Page(imgIndex + index, imageUrl = element.attr("abs:src")))
+            }
+        }
+
+        return pageList
+    }
+
+    override fun imageUrlParse(document: Document) = ""
+
+    override fun imageRequest(page: Page): Request {
+        val imgHeaders = headersBuilder().apply {
+            add("Accept", "image/avif,image/webp,*/*")
+            add("Accept-Language", "en-US,en;q=0.5")
+            add("DNT", "1")
+            add("Host", page.imageUrl!!.substringAfter("://").substringBefore("/"))
+            add("Sec-Fetch-Dest", "image")
+            add("Sec-Fetch-Mode", "no-cors")
+            add("Sec-Fetch-Site", "cross-site")
+        }.build()
+
+        return GET(page.imageUrl!!, imgHeaders)
+    }
+
+    // ============================= Utilities ==============================
+
+    private inline fun <reified T> Response.parseAs(): T = use {
+        json.decodeFromStream(it.body.byteStream())
+    }
+}